<PAGE> PAGE 1
000 A000000 06/30/98
000 C000000 0000060332
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 3.0
000 J000000 U
001 A000000 CGM CAPITAL DEVELOPMENT FUND
001 B000000 811-933
001 C000000 6178597714
002 A000000 ONE INTERNATIONAL PLACE
002 B000000 BOSTON
002 C000000 MA
002 D010000 02110
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 Y
007 B000000 1
007 C010100 1
007 C020100 CGM CAPITAL DEVELOPMENT FUND
007 C030100 N
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
020 A000001 WERTHEIM & CO., INC.
020 B000001 13-2697272
020 C000001 447
020 A000002 LEHMAN BOTHERS
020 C000002 118
020 A000003 ALEX BROWN & SONS
020 B000003 52-0256630
020 C000003 114
020 A000004 CS FIRST BOSTON CORP.
020 C000004 137
020 A000005 MONTGOMERY SECURITIES
020 B000005 94-1701676
020 C000005 128
020 A000006 ROBINSON HUMPHREY
020 B000006 58-1472560
020 C000006 130
020 A000007 HAMBRECH
<PAGE> PAGE 2
020 C000007 120
020 A000008 FURMAN, SELZ, MAGERDIETZ & BIRNE
020 C000008 247
020 A000009 TUCKER ANTHONY
020 C000009 136
020 A000010 BEAR STEARNS & CO
020 B000010 13-4946705
020 C000010 167
021 000000 3530
022 A000001 ABN AMRO CHICAGO CORP.
022 C000001 4104
022 D000001 0
022 A000002 AMERICAN EXPRESS CO.
022 B000002 13-2518466
022 C000002 380035
022 D000002 0
022 A000003 DONALDSON LUFKIN & JENRETTE & CO.
022 B000003 13-5033225
022 C000003 17160
022 D000003 6087
022 A000004 CHEVRON OIL
022 B000004 25-1215010
022 C000004 30970
022 D000004 0
022 A000005 LEHMAN BROTHERS
022 C000005 48444
022 D000005 42136
022 A000006 MONTGOMERY SECURITIES
022 B000006 94-1701676
022 C000006 114688
022 D000006 0
022 A000007 SOUNDVIEW FUNANCIAL GROUP
022 C000007 2374
022 D000007 37114
022 A000008 JP MORGAN SECURITIES
022 C000008 8826
022 D000008 25728
022 A000009 MORGAN STANLEY AND CO.
022 C000009 29538
022 D000009 25329
022 A000010 GOLDMAN SACHS & CO.
022 B000010 13-5108880
022 C000010 10575
022 D000010 12713
023 C000000 1846036
023 D000000 1458987
077 A000000 Y
077 B000000 N
077 C000000 N
077 D000000 N
077 E000000 N
<PAGE> PAGE 3
077 F000000 N
077 G000000 N
077 H000000 N
077 I000000 N
077 J000000 N
077 K000000 N
077 L000000 N
077 M000000 N
077 N000000 N
077 O000000 N
077 P000000 N
077 Q010000 Y
077 Q020000 N
077 Q030000 N
078 000000 N
028 A010100 5184
028 A020100 0
028 A030100 0
028 A040100 5735
028 B010100 2924
028 B020100 0
028 B030100 0
028 B040100 5423
028 C010100 3117
028 C020100 0
028 C030100 0
028 C040100 5546
028 D010100 2036
028 D020100 0
028 D030100 0
028 D040100 8114
028 E010100 1585
028 E020100 0
028 E030100 0
028 E040100 5962
028 F010100 2869
028 F020100 0
028 F030100 0
028 F040100 8815
028 G010100 17715
028 G020100 0
028 G030100 0
028 G040100 39595
028 H000100 0
062 A000100 N
062 B000100 0.0
062 C000100 0.0
062 D000100 0.0
062 E000100 0.0
062 F000100 0.0
062 G000100 0.0
<PAGE> PAGE 4
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 0.0
062 P000100 0.0
062 Q000100 0.0
062 R000100 0.0
070 A010100 Y
070 A020100 N
070 B010100 N
070 B020100 N
070 C010100 N
070 C020100 N
070 D010100 N
070 D020100 N
070 E010100 N
070 E020100 N
070 F010100 N
070 F020100 N
070 G010100 N
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 Y
070 L020100 Y
070 M010100 N
070 M020100 N
070 N010100 N
070 N020100 N
070 O010100 Y
070 O020100 N
070 P010100 N
070 P020100 N
070 Q010100 N
070 Q020100 N
070 R010100 N
070 R020100 N
071 A000100 1431456
071 B000100 1458987
071 C000100 764202
071 D000100 378
<PAGE> PAGE 5
072 A000100 6
072 B000100 92
072 C000100 7831
072 D000100 0
072 E000100 0
072 F000100 3761
072 G000100 26
072 H000100 0
072 I000100 97
072 J000100 60
072 K000100 0
072 L000100 14
072 M000100 26
072 N000100 27
072 O000100 0
072 P000100 0
072 Q000100 0
072 R000100 15
072 S000100 8
072 T000100 0
072 U000100 0
072 V000100 0
072 W000100 1
072 X000100 4035
072 Y000100 0
072 Z000100 3888
072AA000100 121751
072BB000100 0
072CC010100 0
072CC020100 74631
072DD010100 0
072DD020100 0
072EE000100 0
073 A010100 0.0000
073 A020100 0.0000
073 B000100 0.0000
073 C000100 0.0000
074 A000100 4
074 B000100 0
074 C000100 275
074 D000100 0
074 E000100 0
074 F000100 748936
074 G000100 0
074 H000100 0
074 I000100 0
074 J000100 30553
074 K000100 0
074 L000100 956
074 M000100 0
074 N000100 780724
<PAGE> PAGE 6
074 O000100 27930
074 P000100 618
074 Q000100 0
074 R010100 0
074 R020100 0
074 R030100 0
074 R040100 376
074 S000100 0
074 T000100 751800
074 U010100 26068
074 U020100 0
074 V010100 28.84
074 V020100 0.00
074 W000100 0.0000
074 X000100 10803
074 Y000100 0
075 A000100 0
075 B000100 771947
076 000100 0.00
SIGNATURE FRANK STRAUSS
TITLE TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000060332
<NAME> CGM CAPITAL DEVELOPMENT FUND
<SERIES>
<NUMBER> 1
<NAME> CGM CAPITAL DEVELOPMENT FUND
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-END> JUN-30-1998
<INVESTMENTS-AT-COST> 725461689
<INVESTMENTS-AT-VALUE> 749211313
<RECEIVABLES> 31508063
<ASSETS-OTHER> 4351
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 780723727
<PAYABLE-FOR-SECURITIES> 27929981
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 993310
<TOTAL-LIABILITIES> 28923291
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 602532457
<SHARES-COMMON-STOCK> 26067515
<SHARES-COMMON-PRIOR> 26808321
<ACCUMULATED-NII-CURRENT> 3888210
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 121630145
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 23749624
<NET-ASSETS> 751800436
<DIVIDEND-INCOME> 7831603
<INTEREST-INCOME> 91794
<OTHER-INCOME> 0
<EXPENSES-NET> 4035187
<NET-INVESTMENT-INCOME> 3888210
<REALIZED-GAINS-CURRENT> 121750602
<APPREC-INCREASE-CURRENT> (74630611)
<NET-CHANGE-FROM-OPS> 51008201
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 620357
<NUMBER-OF-SHARES-REDEEMED> 1361163
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 29127532
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (120457)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 3760584
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 4035187
<AVERAGE-NET-ASSETS> 771947271
<PER-SHARE-NAV-BEGIN> 26.96
<PER-SHARE-NII> 0.15
<PER-SHARE-GAIN-APPREC> 1.73
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 28.84
<EXPENSE-RATIO> 1.05
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>