<PAGE> PAGE 1
000 A000000 03/31/1999
000 C000000 0000854904
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 6.1
000 J000000 A
001 A000000 MSDW PRIME INCOME TRUST
001 B000000 811-5898
001 C000000 2123921600
002 A000000 2 WORLD TRADE CENTER
002 B000000 NEW YORK
002 C000000 NY
002 D010000 10048
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 N
007 B000000 0
007 C010100 1
007 C010200 2
007 C010300 3
007 C010400 4
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
008 A000001 MORGAN STANLEY DEAN WITTER ADVISORS INC.
008 B000001 A
008 C000001 801-42061
008 D010001 NEW YORK
008 D020001 NY
008 D030001 10048
010 A000001 MORGAN STANLEY DEAN WITTER SERVICES COMPANY
010 C010001 NY
010 C020001 NY
010 C030001 10048
011 A000001 MORGAN STANLEY DEAN WITTER DISTRIBUTORS INC.
011 B000001 8-45262
011 C010001 NEW YORK
011 C020001 NY
011 C030001 10048
012 A000001 MORGAN STANLEY DEAN WITTER TRUST FSB
012 B000001 84-1785
012 C010001 JERSEY CITY
012 C020001 NJ
<PAGE> PAGE 2
012 C030001 07311
013 A000001 PRICEWATERHOUSECOOPERS LLP
013 B010001 NEW YORK
013 B020001 NY
013 B030001 10036
014 A000001 DEAN WITTER REYNOLDS INC.
014 B000001 8-14172
014 A000002 MORGAN STANLEY & CO. INCORPORATED
014 B000002 8-15869
015 A000001 THE BANK OF NEW YORK
015 B000001 C
015 C010001 NEW YORK
015 C020001 NY
015 C030001 10286
015 E010001 X
018 000000 Y
019 A000000 Y
019 B000000 121
019 C000000 MSDW-FUNDS
020 C000001 0
020 C000002 0
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 0
022 A000001 BANK OF NEW YORK (THE)
022 B000001 13-5160382
022 C000001 1802219
022 D000001 0
022 A000002 FORD MOTOR CREDIT CO.
022 B000002 36-1612444
022 C000002 854701
022 D000002 0
022 A000003 AMERICAN EXPRESS CREDIT CORP.
022 B000003 11-1988350
022 C000003 834923
022 D000003 0
022 A000004 GENERAL MOTORS ACCEPTANCE CORP.
022 B000004 38-0572512
022 C000004 475213
022 D000004 0
022 A000005 GENERAL ELECTRIC CO.
022 B000005 14-0689340
022 C000005 431063
022 D000005 0
022 A000006 MORGAN (J.P.) SECURITIES INC.
<PAGE> PAGE 3
022 B000006 13-3224016
022 C000006 285548
022 D000006 0
022 A000007 CITIGROUP INC.
022 B000007 52-1568099
022 C000007 202757
022 D000007 0
022 A000008 GENERAL ELECTRIC CAPITAL CORP.
022 B000008 13-1500700
022 C000008 163598
022 D000008 0
022 A000009 MERRILL LYNCH, PIERCE FENNER & SMITH INC.
022 B000009 13-5674085
022 C000009 155991
022 D000009 0
022 A000010 LEHMAN BROTHERS INC.
022 B000010 13-2518466
022 C000010 138229
022 D000010 8618
023 C000000 6466664
023 D000000 64048
024 000000 Y
025 A000001 AMERICAN EXPRESS CREDIT CORP.
025 B000001 11-1988350
025 C000001 D
025 D000001 21992
025 A000002 BANK OF NEW YORK (THE)
025 B000002 13-5160382
025 C000002 D
025 D000002 4370
025 A000003 FORD MOTOR CREDIT CO.
025 B000003 38-1612444
025 C000003 D
025 D000003 67942
025 A000004 GENERAL ELECTRIC CAPITAL CORP.
025 B000004 13-1500700
025 C000004 D
025 D000004 78925
025 D000005 0
025 D000006 0
025 D000007 0
025 D000008 0
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
<PAGE> PAGE 4
027 000000 N
028 A010000 0
028 A020000 0
028 A030000 0
028 A040000 0
028 B010000 0
028 B020000 0
028 B030000 0
028 B040000 0
028 C010000 0
028 C020000 0
028 C030000 0
028 C040000 0
028 D010000 0
028 D020000 0
028 D030000 0
028 D040000 0
028 E010000 0
028 E020000 0
028 E030000 0
028 E040000 0
028 F010000 0
028 F020000 0
028 F030000 0
028 F040000 0
028 G010000 0
028 G020000 0
028 G030000 0
028 G040000 0
028 H000000 0
030 A000000 0
030 B000000 0.00
030 C000000 0.00
031 A000000 0
031 B000000 0
032 000000 0
033 000000 0
035 000000 0
036 B000000 0
038 000000 0
042 A000000 0
042 B000000 0
042 C000000 0
042 D000000 0
042 E000000 0
042 F000000 0
042 G000000 0
042 H000000 0
043 000000 0
044 000000 0
045 000000 Y
<PAGE> PAGE 5
046 000000 N
047 000000 Y
048 000000 0.000
048 A010000 500000
048 A020000 0.900
048 B010000 1000000
048 B020000 0.850
048 C010000 1000000
048 C020000 0.825
048 D010000 0
048 D020000 0.000
048 E010000 0
048 E020000 0.000
048 F010000 0
048 F020000 0.000
048 G010000 0
048 G020000 0.000
048 H010000 0
048 H020000 0.000
048 I010000 0
048 I020000 0.000
048 J010000 0
048 J020000 0.000
048 K010000 2500000
048 K020000 0.800
049 000000 N
050 000000 N
051 000000 N
052 000000 N
053 A000000 N
054 A000000 Y
054 B000000 Y
054 C000000 Y
054 D000000 N
054 E000000 N
054 F000000 N
054 G000000 Y
054 H000000 Y
054 I000000 N
054 J000000 Y
054 K000000 N
054 L000000 Y
054 M000000 Y
054 N000000 N
054 O000000 N
055 A000000 N
055 B000000 N
056 000000 Y
057 000000 N
058 A000000 N
059 000000 Y
<PAGE> PAGE 6
060 A000000 N
060 B000000 N
061 000000 1000
062 A000000 Y
062 B000000 0.0
062 C000000 0.0
062 D000000 0.2
062 E000000 0.0
062 F000000 0.0
062 G000000 0.0
062 H000000 0.0
062 I000000 7.4
062 J000000 0.0
062 K000000 0.0
062 L000000 0.0
062 M000000 0.0
062 N000000 0.0
062 O000000 0.0
062 P000000 0.0
062 Q000000 90.0
062 R000000 0.0
063 A000000 0
063 B000000 5.9
064 A000000 N
064 B000000 Y
065 000000 N
066 A000000 N
067 000000 N
068 A000000 N
068 B000000 N
069 000000 N
070 A010000 Y
070 A020000 Y
070 B010000 N
070 B020000 N
070 C010000 Y
070 C020000 N
070 D010000 N
070 D020000 N
070 E010000 Y
070 E020000 N
070 F010000 N
070 F020000 N
070 G010000 Y
070 G020000 N
070 H010000 N
070 H020000 N
070 I010000 N
070 I020000 N
070 J010000 Y
070 J020000 Y
<PAGE> PAGE 7
070 K010000 Y
070 K020000 N
070 L010000 N
070 L020000 N
070 M010000 N
070 M020000 N
070 N010000 Y
070 N020000 N
070 O010000 Y
070 O020000 N
070 P010000 N
070 P020000 N
070 Q010000 N
070 Q020000 N
070 R010000 N
070 R020000 N
071 A000000 613977
071 B000000 314467
071 C000000 1921854
071 D000000 16
072 A000000 6
072 B000000 84966
072 C000000 0
072 D000000 0
072 E000000 3249
072 F000000 9217
072 G000000 2699
072 H000000 0
072 I000000 464
072 J000000 59
072 K000000 0
072 L000000 157
072 M000000 8
072 N000000 192
072 O000000 0
072 P000000 0
072 Q000000 0
072 R000000 43
072 S000000 295
072 T000000 0
072 U000000 0
072 V000000 0
072 W000000 159
072 X000000 13293
072 Y000000 0
072 Z000000 74922
072AA000000 393
072BB000000 0
072CC010000 0
072CC020000 4906
072DD010000 73229
<PAGE> PAGE 8
072DD020000 0
072EE000000 0
073 A010000 0.3384
073 A020000 0.0000
073 B000000 0.0000
073 C000000 0.0000
074 A000000 6441
074 B000000 4370
074 C000000 205859
074 D000000 2060947
074 E000000 96
074 F000000 1929
074 G000000 0
074 H000000 0
074 I000000 0
074 J000000 0
074 K000000 0
074 L000000 20678
074 M000000 1170
074 N000000 2301490
074 O000000 0
074 P000000 2277
074 Q000000 0
074 R010000 0
074 R020000 0
074 R030000 0
074 R040000 6847
074 S000000 0
074 T000000 2292366
074 U010000 231657
074 U020000 0
074 V010000 9.90
074 V020000 0.00
074 W000000 0.0000
074 X000000 83804
074 Y000000 39855
075 A000000 0
075 B000000 2164739
076 000000 0.00
077 A000000 N
078 000000 N
080 C000000 0
081 B000000 0
082 B000000 0
083 B000000 0
084 B000000 0
086 A010000 38552
086 A020000 381838
086 B010000 8420
086 B020000 83362
086 C010000 0
<PAGE> PAGE 9
086 C020000 0
086 D010000 0
086 D020000 0
086 E010000 0
086 E020000 0
086 F010000 0
086 F020000 0
087 A010000 SHARES OF BENEFICIAL INTEREST
087 A020000 616971-107
087 A030000 XPITX
088 A000000 N
088 B000000 N
088 C000000 N
088 D000000 N
SIGNATURE BARRY FINK
TITLE VICE PRESIDENT
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
MORGAN STANLEY DEAN WITTER PRIME INCOME TRUST
SEMI ANNUAL FDS
3-31-1999
</LEGEND>
<CIK> 0000854904
<NAME> MORGAN STANLEY DEAN WITTER PRIME INCOME TRUST
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> MAR-31-1999
<INVESTMENTS-AT-COST> 2,279,122,719
<INVESTMENTS-AT-VALUE> 2,273,200,709
<RECEIVABLES> 20,677,580
<ASSETS-OTHER> 1,170,308
<OTHER-ITEMS-ASSETS> 6,441,238
<TOTAL-ASSETS> 2,301,489,835
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (9,124,220)
<TOTAL-LIABILITIES> (9,124,220)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 2,307,107,940
<SHARES-COMMON-STOCK> 231,657,384
<SHARES-COMMON-PRIOR> 201,526,077
<ACCUMULATED-NII-CURRENT> 1,140,497
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (9,960,812)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (5,922,010)
<NET-ASSETS> 2,292,365,615
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 84,965,878
<OTHER-INCOME> 3,248,971
<EXPENSES-NET> (13,293,242)
<NET-INVESTMENT-INCOME> 74,921,607
<REALIZED-GAINS-CURRENT> 392,850
<APPREC-INCREASE-CURRENT> (4,905,852)
<NET-CHANGE-FROM-OPS> 70,408,605
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (73,228,701)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 35,285,719
<NUMBER-OF-SHARES-REDEEMED> (8,420,367)
<SHARES-REINVESTED> 3,265,955
<NET-CHANGE-IN-ASSETS> 295,656,187
<ACCUMULATED-NII-PRIOR> (552,409)
<ACCUMULATED-GAINS-PRIOR> (10,353,662)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (9,216,728)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (13,293,242)
<AVERAGE-NET-ASSETS> 2,164,738,984
<PER-SHARE-NAV-BEGIN> 9.91
<PER-SHARE-NII> 0.35
<PER-SHARE-GAIN-APPREC> (0.02)
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> (0.34)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.90
<EXPENSE-RATIO> 1.23
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
</TABLE>
