<PAGE> PAGE 1
000 A000000 12/31/1999
000 C000000 0000225635
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 6.1
000 J000000 A
001 A000000 MERRILL LYNCH MUNICIPAL BOND FUND, INC.
001 B000000 811-2688
001 C000000 6092822800
002 A000000 P.O. BOX 9011
002 B000000 PRINCETON
002 C000000 NJ
002 D010000 08543
002 D020000 9011
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 Y
007 B000000 3
007 C010100 1
007 C020100 NATIONAL PORTFOLIO
007 C030100 N
007 C010200 2
007 C020200 INSURED PORTFOLIO
007 C030200 N
007 C010300 3
007 C020300 LIMITED MATURITY PORTFOLIO
007 C030300 N
007 C010400 4
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
008 A00AA01 FUND ASSET MANAGEMENT, L.P.
008 B00AA01 A
008 C00AA01 801-12485
008 D01AA01 PRINCETON
008 D02AA01 NJ
008 D03AA01 08543
008 D04AA01 9011
011 A00AA01 MERRILL LYNCH FUNDS DISTRIBUTOR, INC.
011 B00AA01 8-14663
011 C01AA01 PRINCETON
011 C02AA01 NJ
011 C03AA01 08543
<PAGE> PAGE 2
011 C04AA01 9011
012 A00AA01 FINANCIAL DATA SERVICES, INC.
012 B00AA01 84-01339
012 C01AA01 JACKSONVILLE
012 C02AA01 FL
012 C03AA01 32246
012 C04AA01 6484
013 A00AA01 DELOITTE & TOUCHE LLP
013 B01AA01 PRINCETON
013 B02AA01 NJ
013 B03AA01 08540
014 A00AA01 MLPF&S AND OTHER ML BROKER/DEALER AFFILIATES
014 B00AA01 8-7221
015 A00AA01 THE BANK OF NEW YORK
015 B00AA01 C
015 C01AA01 NEW YORK
015 C02AA01 NY
015 C03AA01 10286
015 E01AA01 X
015 A00AA02 BANKERS TRUST COMPANY
015 B00AA02 S
015 C01AA02 NEW YORK
015 C02AA02 NY
015 C03AA02 10006
015 E01AA02 X
015 A00AA03 THE CHASE MANHATTAN BANK
015 B00AA03 S
015 C01AA03 NEW YORK
015 C02AA03 NY
015 C03AA03 10017
015 E01AA03 X
015 A00AA04 CUSTODIAL TRUST CO.
015 B00AA04 S
015 C01AA04 NEW YORK
015 C02AA04 NY
015 C03AA04 10167
015 E01AA04 X
015 A00AA05 MORGAN GUARANTY TRUST CO. OF NEW YORK
015 B00AA05 S
015 C01AA05 NEW YORK
015 C02AA05 NY
015 C03AA05 10260
015 E01AA05 X
018 00AA00 Y
019 A00AA00 Y
019 B00AA00 248
019 C00AA00 MERRILLLYN
020 A000001 BZW SECURITIES INC.
020 C000001 26
020 A000002 SALOMON SMITH BARNEY INC.
020 B000002 11-2418191
<PAGE> PAGE 3
020 C000002 16
020 C000003 0
020 C000004 0
020 C000005 0
020 C000006 0
020 C000007 0
020 C000008 0
020 C000009 0
020 C000010 0
021 000000 42
022 A000001 MORGAN STANLEY DEAN WITTER & CO.
022 B000001 13-2655998
022 C000001 632312
022 D000001 647589
022 A000002 MORGAN (J.P.) SECURITIES INC.
022 B000002 13-3224016
022 C000002 223986
022 D000002 182006
022 A000003 CIBC WORLD MARKETS CORP.
022 B000003 13-2798343
022 C000003 180579
022 D000003 183624
022 A000004 PAINEWEBBER INCORPORATED
022 B000004 13-2638166
022 C000004 161996
022 D000004 161012
022 A000005 GOLDMAN, SACHS & CO.
022 B000005 13-5108880
022 C000005 171786
022 D000005 146530
022 A000006 FIRST ALBANY CORPORATION
022 B000006 14-1391446
022 C000006 126492
022 D000006 155760
022 A000007 LEHMAN BROTHERS INC.
022 B000007 13-2518466
022 C000007 116544
022 D000007 118528
022 A000008 SALOMON SMITH BARNEY INC.
022 B000008 11-2418191
022 C000008 96334
022 D000008 59162
022 A000009 BEAR, STEARNS & CO. INC.
022 B000009 13-3299429
022 C000009 30693
022 D000009 94384
022 A000010 FLEET SECURITIES, INC.
022 B000010 13-2967453
022 C000010 26966
022 D000010 88613
023 C000000 2133751
<PAGE> PAGE 4
023 D000000 2403650
024 00AA00 N
026 A000000 N
026 B000000 Y
026 C000000 N
026 D000000 Y
026 E000000 N
026 F000000 N
026 G010000 N
026 G020000 N
026 H000000 N
027 000000 Y
037 00AA00 N
038 00AA00 0
039 00AA00 N
040 00AA00 Y
041 00AA00 Y
049 00AA00 N
050 00AA00 N
051 00AA00 N
052 00AA00 N
053 A00AA00 N
054 A00AA00 Y
054 B00AA00 Y
054 C00AA00 N
054 D00AA00 N
054 E00AA00 N
054 F00AA00 N
054 G00AA00 N
054 H00AA00 Y
054 I00AA00 N
054 J00AA00 Y
054 K00AA00 N
054 L00AA00 N
054 M00AA00 Y
054 N00AA00 N
058 A00AA00 N
059 00AA00 Y
060 A00AA00 Y
060 B00AA00 Y
061 00AA00 0
066 A00AA00 N
067 00AA00 N
068 A00AA00 N
068 B00AA00 N
069 00AA00 N
077 A000000 Y
077 O000000 Y
078 000000 N
028 A010100 8828
028 A020100 3391
<PAGE> PAGE 5
028 A030100 0
028 A040100 28358
028 B010100 6781
028 B020100 2666
028 B030100 0
028 B040100 37878
028 C010100 9872
028 C020100 2649
028 C030100 0
028 C040100 31528
028 D010100 5240
028 D020100 3193
028 D030100 0
028 D040100 26790
028 E010100 18531
028 E020100 2532
028 E030100 0
028 E040100 48804
028 F010100 22819
028 F020100 3445
028 F030100 0
028 F040100 68842
028 G010100 72071
028 G020100 17876
028 G030100 0
028 G040100 242200
028 H000100 20280
029 000100 Y
030 A000100 46
030 B000100 4.00
030 C000100 0.00
031 A000100 5
031 B000100 0
032 000100 0
033 000100 41
034 000100 Y
035 000100 322
036 A000100 N
036 B000100 0
042 A000100 0
042 B000100 0
042 C000100 100
042 D000100 0
042 E000100 0
042 F000100 0
042 G000100 0
042 H000100 0
043 000100 1582
044 000100 0
045 000100 Y
046 000100 N
<PAGE> PAGE 6
047 000100 Y
048 000100 0.000
048 A010100 250000
048 A020100 0.500
048 B010100 150000
048 B020100 0.475
048 C010100 150000
048 C020100 0.475
048 D010100 950000
048 D020100 0.475
048 E010100 0
048 E020100 0.000
048 F010100 0
048 F020100 0.000
048 G010100 0
048 G020100 0.000
048 H010100 0
048 H020100 0.000
048 I010100 0
048 I020100 0.000
048 J010100 0
048 J020100 0.000
048 K010100 1500000
048 K020100 0.475
055 A000100 N
055 B000100 N
056 000100 Y
057 000100 N
062 A000100 Y
062 B000100 0.0
062 C000100 0.0
062 D000100 0.0
062 E000100 5.4
062 F000100 0.0
062 G000100 0.0
062 H000100 0.0
062 I000100 0.0
062 J000100 0.0
062 K000100 0.0
062 L000100 0.0
062 M000100 0.0
062 N000100 0.0
062 O000100 93.2
062 P000100 0.0
062 Q000100 0.0
062 R000100 0.0
063 A000100 0
063 B000100 21.5
064 A000100 Y
064 B000100 N
070 A010100 Y
<PAGE> PAGE 7
070 A020100 N
070 B010100 N
070 B020100 N
070 C010100 N
070 C020100 N
070 D010100 N
070 D020100 N
070 E010100 Y
070 E020100 Y
070 F010100 N
070 F020100 N
070 G010100 Y
070 G020100 N
070 H010100 N
070 H020100 N
070 I010100 N
070 I020100 N
070 J010100 Y
070 J020100 N
070 K010100 Y
070 K020100 N
070 L010100 N
070 L020100 N
070 M010100 N
070 M020100 N
070 N010100 N
070 N020100 N
070 O010100 Y
070 O020100 N
070 P010100 Y
070 P020100 Y
070 Q010100 N
070 Q020100 N
070 R010100 Y
070 R020100 N
071 A000100 494873
071 B000100 621211
071 C000100 1199476
071 D000100 41
072 A000100 6
072 B000100 40486
072 C000100 0
072 D000100 0
072 E000100 0
072 F000100 3108
072 G000100 75
072 H000100 0
072 I000100 260
072 J000100 66
072 K000100 0
072 L000100 27
<PAGE> PAGE 8
072 M000100 8
072 N000100 64
072 O000100 0
072 P000100 0
072 Q000100 0
072 R000100 13
072 S000100 45
072 T000100 1582
072 U000100 0
072 V000100 0
072 W000100 27
072 X000100 5275
072 Y000100 0
072 Z000100 35211
072AA000100 8855
072BB000100 29460
072CC010100 0
072CC020100 68598
072DD010100 25747
072DD020100 9464
072EE000100 0
073 A010100 0.0000
073 A020100 0.0000
073 B000100 0.0000
073 C000100 0.0000
074 A000100 24
074 B000100 0
074 C000100 61950
074 D000100 1074595
074 E000100 0
074 F000100 0
074 G000100 0
074 H000100 0
074 I000100 0
074 J000100 7072
074 K000100 0
074 L000100 21283
074 M000100 113
074 N000100 1165037
074 O000100 0
074 P000100 798
074 Q000100 0
074 R010100 0
074 R020100 0
074 R030100 0
074 R040100 12110
074 S000100 0
074 T000100 1152129
074 U010100 85949
074 U020100 34931
074 V010100 0.00
<PAGE> PAGE 9
074 V020100 0.00
074 W000100 0.0000
074 X000100 33802
074 Y000100 0
075 A000100 0
075 B000100 1282485
076 000100 0.00
028 A010200 9652
028 A020200 3460
028 A030200 0
028 A040200 29785
028 B010200 8968
028 B020200 2758
028 B030200 0
028 B040200 39538
028 C010200 2516
028 C020200 2665
028 C030200 0
028 C040200 34511
028 D010200 8468
028 D020200 3281
028 D030200 0
028 D040200 28355
028 E010200 10120
028 E020200 2631
028 E030200 0
028 E040200 48834
028 F010200 11832
028 F020200 13900
028 F030200 0
028 F040200 53153
028 G010200 51556
028 G020200 28695
028 G030200 0
028 G040200 234176
028 H000200 11015
029 000200 Y
030 A000200 66
030 B000200 4.00
030 C000200 0.00
031 A000200 8
031 B000200 0
032 000200 0
033 000200 58
034 000200 Y
035 000200 187
036 A000200 N
036 B000200 0
042 A000200 0
042 B000200 0
042 C000200 100
<PAGE> PAGE 10
042 D000200 0
042 E000200 0
042 F000200 0
042 G000200 0
042 H000200 0
043 000200 1582
044 000200 0
045 000200 Y
046 000200 N
047 000200 Y
048 000200 0.000
048 A010200 250000
048 A020200 0.400
048 B010200 150000
048 B020200 0.375
048 C010200 150000
048 C020200 0.375
048 D010200 950000
048 D020200 0.375
048 E010200 0
048 E020200 0.000
048 F010200 0
048 F020200 0.000
048 G010200 0
048 G020200 0.000
048 H010200 0
048 H020200 0.000
048 I010200 0
048 I020200 0.000
048 J010200 0
048 J020200 0.000
048 K010200 1500000
048 K020200 0.350
055 A000200 Y
055 B000200 N
056 000200 Y
057 000200 N
062 A000200 Y
062 B000200 0.0
062 C000200 0.0
062 D000200 0.0
062 E000200 5.7
062 F000200 0.0
062 G000200 0.0
062 H000200 0.0
062 I000200 0.0
062 J000200 0.0
062 K000200 0.0
062 L000200 0.0
062 M000200 0.0
062 N000200 0.0
<PAGE> PAGE 11
062 O000200 94.5
062 P000200 0.0
062 Q000200 0.0
062 R000200 0.0
063 A000200 0
063 B000200 19.9
064 A000200 Y
064 B000200 N
070 A010200 Y
070 A020200 N
070 B010200 N
070 B020200 N
070 C010200 N
070 C020200 N
070 D010200 N
070 D020200 N
070 E010200 Y
070 E020200 Y
070 F010200 N
070 F020200 N
070 G010200 Y
070 G020200 N
070 H010200 N
070 H020200 N
070 I010200 N
070 I020200 N
070 J010200 Y
070 J020200 N
070 K010200 Y
070 K020200 N
070 L010200 N
070 L020200 N
070 M010200 N
070 M020200 N
070 N010200 N
070 N020200 N
070 O010200 Y
070 O020200 N
070 P010200 Y
070 P020200 Y
070 Q010200 N
070 Q020200 N
070 R010200 Y
070 R020200 N
071 A000200 729722
071 B000200 809402
071 C000200 1485091
071 D000200 49
072 A000200 6
072 B000200 46276
072 C000200 0
<PAGE> PAGE 12
072 D000200 0
072 E000200 0
072 F000200 2965
072 G000200 96
072 H000200 0
072 I000200 261
072 J000200 82
072 K000200 0
072 L000200 35
072 M000200 10
072 N000200 32
072 O000200 0
072 P000200 0
072 Q000200 0
072 R000200 14
072 S000200 21
072 T000200 1582
072 U000200 0
072 V000200 0
072 W000200 48
072 X000200 5146
072 Y000200 0
072 Z000200 41130
072AA000200 5115
072BB000200 64379
072CC010200 0
072CC020200 37355
072DD010200 32374
072DD020200 8756
072EE000200 22021
073 A010200 0.0000
073 A020200 0.0000
073 B000200 0.0000
073 C000200 0.0000
074 A000200 85
074 B000200 0
074 C000200 83545
074 D000200 1375595
074 E000200 0
074 F000200 0
074 G000200 0
074 H000200 0
074 I000200 0
074 J000200 305
074 K000200 0
074 L000200 24920
074 M000200 791
074 N000200 1485241
074 O000200 5974
074 P000200 775
074 Q000200 0
<PAGE> PAGE 13
074 R010200 0
074 R020200 0
074 R030200 0
074 R040200 22488
074 S000200 0
074 T000200 1456004
074 U010200 155116
074 U020200 46438
074 V010200 0.00
074 V020200 0.00
074 W000200 0.0000
074 X000200 33092
074 Y000200 0
075 A000200 0
075 B000200 1605361
076 000200 0.00
028 A010300 3081
028 A020300 743
028 A030300 0
028 A040300 9493
028 B010300 4452
028 B020300 570
028 B030300 0
028 B040300 24428
028 C010300 2211
028 C020300 571
028 C030300 0
028 C040300 8342
028 D010300 3202
028 D020300 710
028 D030300 0
028 D040300 6651
028 E010300 783
028 E020300 567
028 E030300 0
028 E040300 6866
028 F010300 10577
028 F020300 787
028 F030300 0
028 F040300 21399
028 G010300 24306
028 G020300 3948
028 G030300 0
028 G040300 77179
028 H000300 4384
029 000300 Y
030 A000300 9
030 B000300 1.00
030 C000300 0.00
031 A000300 1
031 B000300 0
<PAGE> PAGE 14
032 000300 0
033 000300 8
034 000300 Y
035 000300 15
036 A000300 N
036 B000300 0
042 A000300 0
042 B000300 0
042 C000300 100
042 D000300 0
042 E000300 0
042 F000300 0
042 G000300 0
042 H000300 0
043 000300 113
044 000300 0
045 000300 Y
046 000300 N
047 000300 Y
048 000300 0.000
048 A010300 250000
048 A020300 0.400
048 B010300 150000
048 B020300 0.375
048 C010300 150000
048 C020300 0.350
048 D010300 950000
048 D020300 0.325
048 E010300 0
048 E020300 0.000
048 F010300 0
048 F020300 0.000
048 G010300 0
048 G020300 0.000
048 H010300 0
048 H020300 0.000
048 I010300 0
048 I020300 0.000
048 J010300 0
048 J020300 0.000
048 K010300 1500000
048 K020300 0.325
055 A000300 Y
055 B000300 N
056 000300 Y
057 000300 N
062 A000300 Y
062 B000300 0.0
062 C000300 0.0
062 D000300 0.0
062 E000300 29.6
<PAGE> PAGE 15
062 F000300 0.0
062 G000300 0.0
062 H000300 0.0
062 I000300 0.0
062 J000300 0.0
062 K000300 0.0
062 L000300 0.0
062 M000300 0.0
062 N000300 0.0
062 O000300 69.6
062 P000300 0.0
062 Q000300 0.0
062 R000300 0.0
063 A000300 0
063 B000300 1.7
064 A000300 Y
064 B000300 N
070 A010300 Y
070 A020300 N
070 B010300 N
070 B020300 N
070 C010300 N
070 C020300 N
070 D010300 N
070 D020300 N
070 E010300 Y
070 E020300 N
070 F010300 N
070 F020300 N
070 G010300 Y
070 G020300 N
070 H010300 N
070 H020300 N
070 I010300 N
070 I020300 N
070 J010300 Y
070 J020300 N
070 K010300 Y
070 K020300 N
070 L010300 N
070 L020300 N
070 M010300 N
070 M020300 N
070 N010300 N
070 N020300 N
070 O010300 Y
070 O020300 N
070 P010300 Y
070 P020300 N
070 Q010300 N
070 Q020300 N
<PAGE> PAGE 16
070 R010300 Y
070 R020300 N
071 A000300 104108
071 B000300 147048
071 C000300 327023
071 D000300 32
072 A000300 6
072 B000300 7681
072 C000300 0
072 D000300 0
072 E000300 0
072 F000300 615
072 G000300 20
072 H000300 0
072 I000300 45
072 J000300 20
072 K000300 0
072 L000300 7
072 M000300 4
072 N000300 13
072 O000300 0
072 P000300 0
072 Q000300 0
072 R000300 13
072 S000300 -6
072 T000300 113
072 U000300 0
072 V000300 0
072 W000300 10
072 X000300 854
072 Y000300 0
072 Z000300 6827
072AA000300 145
072BB000300 204
072CC010300 0
072CC020300 2380
072DD010300 6081
072DD020300 747
072EE000300 0
073 A010300 0.0000
073 A020300 0.0000
073 B000300 0.0000
073 C000300 0.0000
074 A000300 23
074 B000300 0
074 C000300 99781
074 D000300 234675
074 E000300 0
074 F000300 0
074 G000300 0
074 H000300 0
<PAGE> PAGE 17
074 I000300 0
074 J000300 15
074 K000300 0
074 L000300 5238
074 M000300 68
074 N000300 339800
074 O000300 0
074 P000300 130
074 Q000300 0
074 R010300 0
074 R020300 0
074 R030300 0
074 R040300 2520
074 S000300 0
074 T000300 337150
074 U010300 29845
074 U020300 4393
074 V010300 0.00
074 V020300 0.00
074 W000300 0.0000
074 X000300 5322
074 Y000300 0
075 A000300 0
075 B000300 362049
076 000300 0.00
SIGNATURE DONALD C. BURKE
TITLE TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 011
<NAME> NATIONAL PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1183946176
<INVESTMENTS-AT-VALUE> 1136544660
<RECEIVABLES> 28355465
<ASSETS-OTHER> 136457
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1165036582
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 12907667
<TOTAL-LIABILITIES> 12907667
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1230766437
<SHARES-COMMON-STOCK> 77029458
<SHARES-COMMON-PRIOR> 85914836
<ACCUMULATED-NII-CURRENT> (31236006)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (47401516)
<NET-ASSETS> 734220044
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 40485870
<OTHER-INCOME> 0
<EXPENSES-NET> (5274868)
<NET-INVESTMENT-INCOME> 35211002
<REALIZED-GAINS-CURRENT> (20605064)
<APPREC-INCREASE-CURRENT> (68598086)
<NET-CHANGE-FROM-OPS> (53992148)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (23227290)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1530697
<NUMBER-OF-SHARES-REDEEMED> (11634798)
<SHARES-REINVESTED> 1218723
<NET-CHANGE-IN-ASSETS> (241456208)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (10034915)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (596027)
<GROSS-ADVISORY-FEES> 3108367
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5274868
<AVERAGE-NET-ASSETS> 809209154
<PER-SHARE-NAV-BEGIN> 10.22
<PER-SHARE-NII> .28
<PER-SHARE-GAIN-APPREC> (.69)
<PER-SHARE-DIVIDEND> (.28)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.53
<EXPENSE-RATIO> .56
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 012
<NAME> NATIONAL PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1183946176
<INVESTMENTS-AT-VALUE> 1136544660
<RECEIVABLES> 28355465
<ASSETS-OTHER> 136457
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1165036582
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 12907667
<TOTAL-LIABILITIES> 12907667
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1230766437
<SHARES-COMMON-STOCK> 31022419
<SHARES-COMMON-PRIOR> 36679185
<ACCUMULATED-NII-CURRENT> (31236006)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (47401516)
<NET-ASSETS> 295595355
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 40485870
<OTHER-INCOME> 0
<EXPENSES-NET> (5274868)
<NET-INVESTMENT-INCOME> 35211002
<REALIZED-GAINS-CURRENT> (20605064)
<APPREC-INCREASE-CURRENT> (68598086)
<NET-CHANGE-FROM-OPS> (53992148)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (8390880)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 2211145
<NUMBER-OF-SHARES-REDEEMED> (8282991)
<SHARES-REINVESTED> 415080
<NET-CHANGE-IN-ASSETS> (241456208)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (10034915)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (596027)
<GROSS-ADVISORY-FEES> 3108367
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5274868
<AVERAGE-NET-ASSETS> 337823648
<PER-SHARE-NAV-BEGIN> 10.21
<PER-SHARE-NII> .24
<PER-SHARE-GAIN-APPREC> (.68)
<PER-SHARE-DIVIDEND> (.24)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.53
<EXPENSE-RATIO> 1.32
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 013
<NAME> NATIONAL PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1183946176
<INVESTMENTS-AT-VALUE> 1136544660
<RECEIVABLES> 28355465
<ASSETS-OTHER> 136457
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1165036582
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 12907667
<TOTAL-LIABILITIES> 12907667
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1230766437
<SHARES-COMMON-STOCK> 3908668
<SHARES-COMMON-PRIOR> 4687233
<ACCUMULATED-NII-CURRENT> (31236006)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (47401516)
<NET-ASSETS> 37263815
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 40485870
<OTHER-INCOME> 0
<EXPENSES-NET> (5274868)
<NET-INVESTMENT-INCOME> 35211002
<REALIZED-GAINS-CURRENT> (20605064)
<APPREC-INCREASE-CURRENT> (68598086)
<NET-CHANGE-FROM-OPS> (53992148)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (1072996)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 445953
<NUMBER-OF-SHARES-REDEEMED> (1288792)
<SHARES-REINVESTED> 64274
<NET-CHANGE-IN-ASSETS> (241456208)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (10034915)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (596027)
<GROSS-ADVISORY-FEES> 3108367
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5274868
<AVERAGE-NET-ASSETS> 43637634
<PER-SHARE-NAV-BEGIN> 10.22
<PER-SHARE-NII> .24
<PER-SHARE-GAIN-APPREC> (.69)
<PER-SHARE-DIVIDEND> (.24)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.53
<EXPENSE-RATIO> 1.37
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 014
<NAME> NATIONAL PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1183946176
<INVESTMENTS-AT-VALUE> 1136544660
<RECEIVABLES> 28355465
<ASSETS-OTHER> 136457
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1165036582
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 12907667
<TOTAL-LIABILITIES> 12907667
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1230766437
<SHARES-COMMON-STOCK> 8919187
<SHARES-COMMON-PRIOR> 9118625
<ACCUMULATED-NII-CURRENT> (31236006)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (47401516)
<NET-ASSETS> 85049701
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 40485870
<OTHER-INCOME> 0
<EXPENSES-NET> (5274868)
<NET-INVESTMENT-INCOME> 35211002
<REALIZED-GAINS-CURRENT> (20605064)
<APPREC-INCREASE-CURRENT> (68598086)
<NET-CHANGE-FROM-OPS> (53992148)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (2519836)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 4192725
<NUMBER-OF-SHARES-REDEEMED> (4519125)
<SHARES-REINVESTED> 126962
<NET-CHANGE-IN-ASSETS> (241456208)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (10034915)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (596027)
<GROSS-ADVISORY-FEES> 3108367
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5274868
<AVERAGE-NET-ASSETS> 91814568
<PER-SHARE-NAV-BEGIN> 10.22
<PER-SHARE-NII> .27
<PER-SHARE-GAIN-APPREC> (.68)
<PER-SHARE-DIVIDEND> (.27)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.54
<EXPENSE-RATIO> .81
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 021
<NAME> INSURED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1466052859
<INVESTMENTS-AT-VALUE> 1459140430
<RECEIVABLES> 25224970
<ASSETS-OTHER> 875775
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1485241175
<PAYABLE-FOR-SECURITIES> 5974057
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 23263604
<TOTAL-LIABILITIES> 29237661
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1522447329
<SHARES-COMMON-STOCK> 142766805
<SHARES-COMMON-PRIOR> 156170176
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (59531386)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (6912429)
<NET-ASSETS> 1031506187
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 46275831
<OTHER-INCOME> 0
<EXPENSES-NET> (5145457)
<NET-INVESTMENT-INCOME> 41130374
<REALIZED-GAINS-CURRENT> (59263882)
<APPREC-INCREASE-CURRENT> (37355043)
<NET-CHANGE-FROM-OPS> (55488551)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (30168001)
<DISTRIBUTIONS-OF-GAINS> (15607942)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 761509
<NUMBER-OF-SHARES-REDEEMED> (16860047)
<SHARES-REINVESTED> 2695167
<NET-CHANGE-IN-ASSETS> (272565197)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 21753555
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2965275
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5145457
<AVERAGE-NET-ASSETS> 1133381390
<PER-SHARE-NAV-BEGIN> 7.79
<PER-SHARE-NII> .20
<PER-SHARE-GAIN-APPREC> (.45)
<PER-SHARE-DIVIDEND> (.20)
<PER-SHARE-DISTRIBUTIONS> (.11)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.23
<EXPENSE-RATIO> .43
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 022
<NAME> INSURED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1466052859
<INVESTMENTS-AT-VALUE> 1459140430
<RECEIVABLES> 25224970
<ASSETS-OTHER> 875775
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1485241175
<PAYABLE-FOR-SECURITIES> 5974057
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 23263604
<TOTAL-LIABILITIES> 29237661
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1522447329
<SHARES-COMMON-STOCK> 44552487
<SHARES-COMMON-PRIOR> 53207445
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (59531386)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (6912429)
<NET-ASSETS> 321682490
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 46275831
<OTHER-INCOME> 0
<EXPENSES-NET> (5145457)
<NET-INVESTMENT-INCOME> 41130374
<REALIZED-GAINS-CURRENT> (59263882)
<APPREC-INCREASE-CURRENT> (37355043)
<NET-CHANGE-FROM-OPS> (55488551)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (8409016)
<DISTRIBUTIONS-OF-GAINS> (4878687)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 2109929
<NUMBER-OF-SHARES-REDEEMED> (11676320)
<SHARES-REINVESTED> 911433
<NET-CHANGE-IN-ASSETS> (272565197)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 21753555
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2965275
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5145457
<AVERAGE-NET-ASSETS> 369689763
<PER-SHARE-NAV-BEGIN> 7.78
<PER-SHARE-NII> .17
<PER-SHARE-GAIN-APPREC> (.45)
<PER-SHARE-DIVIDEND> (.17)
<PER-SHARE-DISTRIBUTIONS> (.11)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.22
<EXPENSE-RATIO> 1.19
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 023
<NAME> INSURED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1466052859
<INVESTMENTS-AT-VALUE> 1459140430
<RECEIVABLES> 25224970
<ASSETS-OTHER> 875775
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1485241175
<PAYABLE-FOR-SECURITIES> 5974057
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 23263604
<TOTAL-LIABILITIES> 29237661
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1522447329
<SHARES-COMMON-STOCK> 1885763
<SHARES-COMMON-PRIOR> 2164467
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (59531386)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (6912429)
<NET-ASSETS> 13618549
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 46275831
<OTHER-INCOME> 0
<EXPENSES-NET> (5145457)
<NET-INVESTMENT-INCOME> 41130374
<REALIZED-GAINS-CURRENT> (59263882)
<APPREC-INCREASE-CURRENT> (37355043)
<NET-CHANGE-FROM-OPS> (55488551)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (346899)
<DISTRIBUTIONS-OF-GAINS> (207962)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 330296
<NUMBER-OF-SHARES-REDEEMED> (648578)
<SHARES-REINVESTED> 39578
<NET-CHANGE-IN-ASSETS> (272565197)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 21753555
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2965275
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5145457
<AVERAGE-NET-ASSETS> 15417552
<PER-SHARE-NAV-BEGIN> 7.78
<PER-SHARE-NII> .17
<PER-SHARE-GAIN-APPREC> (.45)
<PER-SHARE-DIVIDEND> (.17)
<PER-SHARE-DISTRIBUTIONS> (.11)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.22
<EXPENSE-RATIO> 1.24
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 024
<NAME> INSURED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1466052859
<INVESTMENTS-AT-VALUE> 1459140430
<RECEIVABLES> 25224970
<ASSETS-OTHER> 875775
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1485241175
<PAYABLE-FOR-SECURITIES> 5974057
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 23263604
<TOTAL-LIABILITIES> 29237661
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1522447329
<SHARES-COMMON-STOCK> 12348950
<SHARES-COMMON-PRIOR> 10433764
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (59531386)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (6912429)
<NET-ASSETS> 89196288
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 46275831
<OTHER-INCOME> 0
<EXPENSES-NET> (5145457)
<NET-INVESTMENT-INCOME> 41130374
<REALIZED-GAINS-CURRENT> (59263882)
<APPREC-INCREASE-CURRENT> (37355043)
<NET-CHANGE-FROM-OPS> (55488551)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (2206458)
<DISTRIBUTIONS-OF-GAINS> (1326468)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 7187656
<NUMBER-OF-SHARES-REDEEMED> (5508070)
<SHARES-REINVESTED> 235600
<NET-CHANGE-IN-ASSETS> (272565197)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 21753555
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2965275
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5145457
<AVERAGE-NET-ASSETS> 86872447
<PER-SHARE-NAV-BEGIN> 7.79
<PER-SHARE-NII> .19
<PER-SHARE-GAIN-APPREC> (.46)
<PER-SHARE-DIVIDEND> (.19)
<PER-SHARE-DISTRIBUTIONS> (.11)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.22
<EXPENSE-RATIO> .68
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 031
<NAME> LIMITED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 336591481
<INVESTMENTS-AT-VALUE> 334456355
<RECEIVABLES> 5252691
<ASSETS-OTHER> 91366
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 339800412
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2650292
<TOTAL-LIABILITIES> 2650292
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 341212092
<SHARES-COMMON-STOCK> 23147381
<SHARES-COMMON-PRIOR> 26423567
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (1622169)
<OVERDISTRIBUTION-GAINS> (304677)
<ACCUM-APPREC-OR-DEPREC> (2135126)
<NET-ASSETS> 227920418
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 7681344
<OTHER-INCOME> 0
<EXPENSES-NET> (854065)
<NET-INVESTMENT-INCOME> 6827279
<REALIZED-GAINS-CURRENT> (58908)
<APPREC-INCREASE-CURRENT> (2380447)
<NET-CHANGE-FROM-OPS> 4387924
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (4755157)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 277669
<NUMBER-OF-SHARES-REDEEMED> (3829268)
<SHARES-REINVESTED> 275413
<NET-CHANGE-IN-ASSETS> (51364204)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1563261)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (304677)
<GROSS-ADVISORY-FEES> 614968
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 854065
<AVERAGE-NET-ASSETS> 247978196
<PER-SHARE-NAV-BEGIN> 9.91
<PER-SHARE-NII> .19
<PER-SHARE-GAIN-APPREC> (.06)
<PER-SHARE-DIVIDEND> (.19)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.85
<EXPENSE-RATIO> .40
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 032
<NAME> LIMITED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 336591481
<INVESTMENTS-AT-VALUE> 334456355
<RECEIVABLES> 5252691
<ASSETS-OTHER> 91366
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 339800412
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2650292
<TOTAL-LIABILITIES> 2650292
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 341212092
<SHARES-COMMON-STOCK> 4331778
<SHARES-COMMON-PRIOR> 4329348
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (1622169)
<OVERDISTRIBUTION-GAINS> (304677)
<ACCUM-APPREC-OR-DEPREC> (2135126)
<NET-ASSETS> 42660512
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 7681344
<OTHER-INCOME> 0
<EXPENSES-NET> (854065)
<NET-INVESTMENT-INCOME> 6827279
<REALIZED-GAINS-CURRENT> (58908)
<APPREC-INCREASE-CURRENT> (2380447)
<NET-CHANGE-FROM-OPS> 4387924
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (736667)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 758883
<NUMBER-OF-SHARES-REDEEMED> (806082)
<SHARES-REINVESTED> 49629
<NET-CHANGE-IN-ASSETS> (51364204)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1563261)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (304677)
<GROSS-ADVISORY-FEES> 614968
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 854065
<AVERAGE-NET-ASSETS> 42432538
<PER-SHARE-NAV-BEGIN> 9.92
<PER-SHARE-NII> .17
<PER-SHARE-GAIN-APPREC> (.07)
<PER-SHARE-DIVIDEND> (.17)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.85
<EXPENSE-RATIO> .76
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 033
<NAME> LIMITED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 336591481
<INVESTMENTS-AT-VALUE> 334456355
<RECEIVABLES> 5252691
<ASSETS-OTHER> 91366
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 339800412
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2650292
<TOTAL-LIABILITIES> 2650292
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 341212092
<SHARES-COMMON-STOCK> 61007
<SHARES-COMMON-PRIOR> 44228
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (1622169)
<OVERDISTRIBUTION-GAINS> (304677)
<ACCUM-APPREC-OR-DEPREC> (2135126)
<NET-ASSETS> 598742
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 7681344
<OTHER-INCOME> 0
<EXPENSES-NET> (854065)
<NET-INVESTMENT-INCOME> 6827279
<REALIZED-GAINS-CURRENT> (58908)
<APPREC-INCREASE-CURRENT> (2380447)
<NET-CHANGE-FROM-OPS> 4387924
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (10016)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 60596
<NUMBER-OF-SHARES-REDEEMED> (44539)
<SHARES-REINVESTED> 722
<NET-CHANGE-IN-ASSETS> (51364204)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1563261)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (304677)
<GROSS-ADVISORY-FEES> 614968
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 854065
<AVERAGE-NET-ASSETS> 577159
<PER-SHARE-NAV-BEGIN> 9.88
<PER-SHARE-NII> .17
<PER-SHARE-GAIN-APPREC> (.07)
<PER-SHARE-DIVIDEND> (.17)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.81
<EXPENSE-RATIO> .76
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225635
<NAME> MERRILL LYNCH MUNICIPAL BOND FUND, INC.
<SERIES>
<NUMBER> 034
<NAME> LIMITED PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 336591481
<INVESTMENTS-AT-VALUE> 334456355
<RECEIVABLES> 5252691
<ASSETS-OTHER> 91366
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 339800412
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2650292
<TOTAL-LIABILITIES> 2650292
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 341212092
<SHARES-COMMON-STOCK> 6697529
<SHARES-COMMON-PRIOR> 8386704
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (1622169)
<OVERDISTRIBUTION-GAINS> (304677)
<ACCUM-APPREC-OR-DEPREC> (2135126)
<NET-ASSETS> 65970448
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 7681344
<OTHER-INCOME> 0
<EXPENSES-NET> (854065)
<NET-INVESTMENT-INCOME> 6827279
<REALIZED-GAINS-CURRENT> (58908)
<APPREC-INCREASE-CURRENT> (2380447)
<NET-CHANGE-FROM-OPS> 4387924
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (1325439)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1373595
<NUMBER-OF-SHARES-REDEEMED> (3136361)
<SHARES-REINVESTED> 73591
<NET-CHANGE-IN-ASSETS> (51364204)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1563261)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (304677)
<GROSS-ADVISORY-FEES> 614968
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 854065
<AVERAGE-NET-ASSETS> 71060891
<PER-SHARE-NAV-BEGIN> 9.92
<PER-SHARE-NII> .18
<PER-SHARE-GAIN-APPREC> (.07)
<PER-SHARE-DIVIDEND> (.18)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.85
<EXPENSE-RATIO> .50
</TABLE>
