<PAGE> PAGE 1
000 B000000 05/31/96
000 C000000 0000923757
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 3.0.a
000 J000000 A
001 A000000 DEAN WITTER MID-CAP GROWTH FUND
001 B000000 811-7179
001 C000000 2123922550
002 A000000 TWO 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
007 C011100 11
007 C011200 12
007 C011300 13
007 C011400 14
007 C011500 15
007 C011600 16
007 C011700 17
007 C011800 18
007 C011900 19
007 C012000 20
007 C012100 21
007 C012200 22
007 C012300 23
007 C012400 24
007 C012500 25
007 C012600 26
007 C012700 27
007 C012800 28
007 C012900 29
<PAGE> PAGE 2
007 C013000 30
007 C013100 31
007 C013200 32
007 C013300 33
007 C013400 34
007 C013500 35
007 C013600 36
007 C013700 37
007 C013800 38
007 C013900 39
007 C014000 40
007 C014100 41
007 C014200 42
007 C014300 43
007 C014400 44
007 C014500 45
007 C014600 46
007 C014700 47
007 C014800 48
007 C014900 49
007 C015000 50
007 C015100 51
007 C015200 52
007 C015300 53
007 C015400 54
007 C015500 55
007 C015600 56
007 C015700 57
007 C015800 58
007 C015900 59
007 C016000 60
007 C016100 61
007 C016200 62
007 C016300 63
007 C016400 64
007 C016500 65
007 C016600 66
007 C016700 67
007 C016800 68
007 C016900 69
007 C017000 70
007 C017100 71
007 C017200 72
007 C017300 73
007 C017400 74
007 C017500 75
007 C017600 76
007 C017700 77
007 C017800 78
007 C017900 79
007 C018000 80
<PAGE> PAGE 3
007 C018100 81
007 C018200 82
007 C018300 83
007 C018400 84
007 C018500 85
007 C018600 86
007 C018700 87
007 C018800 88
007 C018900 89
007 C019000 90
008 A000001 DEAN WITTER INTERCAPITAL INC
008 B000001 A
008 C000001 801-42061
008 D010001 NEW YORK
008 D020001 NY
008 D030001 10048
010 A000001 DELETE
011 A000001 DEAN WITTER DISTRIBUTORS INC.
011 B000001 8-45262
011 C010001 NEW YORK
011 C020001 NY
011 C030001 10048
012 A000001 DEAN WITTER TRUST COMPNAY
012 B000001 84-1785
012 C010001 JERSEY CITY
012 C020001 NJ
012 C030001 07311
013 A000001 PRICE WATERHOUSE LLP
013 B010001 NEW YORK
013 B020001 NY
013 B030001 10036
014 A000001 DEAN WITTER REYNOLDS INC.
014 B000001 8-14172
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 DEANWITTER
020 A000001 DEAN WITTER REYNOLDS INC.
020 B000001 94-1671384
020 C000001 115
020 A000002 MERRIL LYNCH,PIERCE,FENNER & SMITH INC.
020 B000002 13-5674085
020 C000002 55
020 A000003 ISTINET CORP.
020 B000003 13-3443395
<PAGE> PAGE 4
020 C000003 46
020 A000004 WEEDER & CO. L.P.
020 B000004 13-3364318
020 C000004 39
020 A000005 MORGAN STANLEY & CO. INC.
020 B000005 13-2655998
020 C000005 38
020 A000006 PAINE WEBBER INC.
020 B000006 13-2638166
020 C000006 35
020 A000007 LEHMAN BROTHERS INC.
020 B000007 13-2518466
020 C000007 34
020 A000008 LAWRENCE (C.J.) MORGAN GRENFELL
020 B000008 13-2730828
020 C000008 32
020 A000009 BEAR STERNS & CO. INC.
020 B000009 13-3299429
020 C000009 31
020 A000010 INTERSTATE JOHNSON LANE CORP.
020 B000010 56-0276690
020 C000010 31
021 000000 965
022 A000001 BA SECURITIES INC.
022 B000001 95-4035346
022 C000001 1220876
022 D000001 0
022 A000002 BANK OF NEW YORK (THE)
022 B000002 13-5160382
022 C000002 359663
022 D000002 0
022 A000003 MORGAN STANLEY & CO. INC.
022 B000003 13-2655998
022 C000003 71539
022 D000003 26115
022 A000004 GOLDMAN, SACHS & CO.
022 B000004 13-5108880
022 C000004 64592
022 D000004 32772
022 A000005 MERRILL LYNCH,PIERCE,FENNER & SMITH,INC.
022 B000005 13-5674085
022 C000005 51552
022 D000005 39812
022 A000006 BROWN (ALEX) & SONS INC.
022 B000006 52-1319768
022 C000006 35996
022 D000006 14892
022 A000007 SMITH BARNEY SHEARSON INC.
022 B000007 13-1912900
022 C000007 23717
022 D000007 24380
<PAGE> PAGE 5
022 A000008 BEAR,STEARNS & CO. INC.
022 B000008 13-3299429
022 C000008 20405
022 D000008 20950
022 A000009 MONTGOMERY SECURITIES
022 B000009 94-1701676
022 C000009 19730
022 D000009 17965
022 A000010 PAINEWEBBER, INC.
022 B000010 13-2638166
022 C000010 18215
022 D000010 18888
023 C000000 2100677
023 D000000 349219
024 000000 N
025 A000001 DELETE
025 D000001 0
025 A000002 DELETE
025 D000002 0
025 D000003 0
025 D000004 0
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 Y
027 000000 Y
028 A010000 17700
028 A020000 15771
028 A030000 0
028 A040000 16940
028 B010000 23587
028 B020000 0
028 B030000 0
028 B040000 12477
028 C010000 22045
028 C020000 0
028 C030000 0
028 C040000 14949
028 D010000 29063
028 D020000 0
028 D030000 0
028 D040000 17304
<PAGE> PAGE 6
028 E010000 34890
028 E020000 0
028 E030000 0
028 E040000 14651
028 F010000 36355
028 F020000 0
028 F030000 0
028 F040000 19309
028 G010000 163640
028 G020000 15771
028 G030000 0
028 G040000 95630
028 H000000 163640
029 000000 N
030 A000000 0
030 B000000 0.00
030 C000000 0.00
031 A000000 0
031 B000000 0
032 000000 0
033 000000 0
034 000000 Y
035 000000 490
036 A000000 N
036 B000000 0
037 000000 N
038 000000 0
039 000000 N
040 000000 Y
041 000000 Y
042 A000000 0
042 B000000 0
042 C000000 100
042 D000000 0
042 E000000 0
042 F000000 0
042 G000000 0
042 H000000 0
043 000000 1958
044 000000 0
045 000000 Y
046 000000 N
047 000000 Y
048 000000 0.750
048 A010000 0
048 A020000 0.000
048 B010000 0
048 B020000 0.000
048 C010000 0
048 C020000 0.000
048 D010000 0
<PAGE> PAGE 7
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 0
048 K020000 0.000
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 Y
055 A000000 Y
055 B000000 N
056 000000 Y
057 000000 N
058 A000000 N
059 000000 Y
060 A000000 Y
060 B000000 Y
061 000000 1000
062 A000000 N
062 B000000 0.0
062 C000000 0.0
062 D000000 0.0
062 E000000 0.0
062 F000000 0.0
062 G000000 0.0
<PAGE> PAGE 8
062 H000000 0.0
062 I000000 0.0
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 0.0
062 R000000 0.0
063 A000000 0
063 B000000 0.0
066 A000000 Y
066 B000000 N
066 C000000 N
066 D000000 Y
066 E000000 N
066 F000000 N
066 G000000 N
067 000000 N
068 A000000 N
068 B000000 N
069 000000 N
070 A010000 Y
070 A020000 Y
070 B010000 Y
070 B020000 N
070 C010000 Y
070 C020000 Y
070 D010000 Y
070 D020000 N
070 E010000 Y
070 E020000 N
070 F010000 Y
070 F020000 N
070 G010000 Y
070 G020000 N
070 H010000 Y
070 H020000 N
070 I010000 N
070 I020000 N
070 J010000 Y
070 J020000 N
070 K010000 N
070 K020000 N
070 L010000 Y
070 L020000 Y
070 M010000 N
070 M020000 N
070 N010000 Y
<PAGE> PAGE 9
070 N020000 N
070 O010000 Y
070 O020000 N
070 P010000 Y
070 P020000 Y
070 Q010000 N
070 Q020000 N
070 R010000 N
070 R020000 N
071 A000000 729117
071 B000000 622252
071 C000000 189778
071 D000000 328
072 A000000 12
072 B000000 1056
072 C000000 893
072 D000000 0
072 E000000 0
072 F000000 1469
072 G000000 0
072 H000000 0
072 I000000 246
072 J000000 91
072 K000000 0
072 L000000 60
072 M000000 18
072 N000000 83
072 O000000 1
072 P000000 0
072 Q000000 0
072 R000000 38
072 S000000 12
072 T000000 1958
072 U000000 30
072 V000000 0
072 W000000 6
072 X000000 4012
072 Y000000 0
072 Z000000 -2063
072AA000000 45085
072BB000000 0
072CC010000 36875
072CC020000 0
072DD010000 0
072DD020000 0
072EE000000 17036
073 A010000 0.0000
073 A020000 0.0000
073 B000000 1.1973
073 C000000 0.0000
074 A000000 0
<PAGE> PAGE 10
074 B000000 3099
074 C000000 0
074 D000000 0
074 E000000 0
074 F000000 301248
074 G000000 0
074 H000000 0
074 I000000 0
074 J000000 6592
074 K000000 4
074 L000000 3265
074 M000000 117
074 N000000 314325
074 O000000 4212
074 P000000 450
074 Q000000 0
074 R010000 0
074 R020000 0
074 R030000 0
074 R040000 391
074 S000000 0
074 T000000 309272
074 U010000 20474
074 U020000 0
074 V010000 15.11
074 V020000 0.00
074 W000000 0.0000
074 X000000 29357
074 Y000000 0
075 A000000 0
075 B000000 195842
076 000000 0.00
077 A000000 Y
077 B000000 Y
077 C000000 N
077 D000000 N
077 E000000 N
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 Y
077 P000000 N
077 Q010000 N
077 Q020000 N
077 Q030000 N
<PAGE> PAGE 11
080 A000000 ICI MUTUAL INSURANCE COMPANY
080 B000000 GULF CHUBB VIGILANT RELIANCE
080 C000000 100000
081 A000000 Y
081 B000000 120
082 A000000 N
082 B000000 0
083 A000000 N
083 B000000 0
084 A000000 N
084 B000000 0
085 A000000 Y
085 B000000 N
086 A010000 0
086 A020000 0
086 B010000 0
086 B020000 0
086 C010000 0
086 C020000 0
086 D010000 0
086 D020000 0
086 E010000 0
086 E020000 0
086 F010000 0
086 F020000 0
SIGNATURE SHELDON CURTIS
TITLE VP & GENERAL COUNSEL
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
dean witter mid-cap growth fund
05/31/96 annual
</LEGEND>
<CIK> 0000923757
<NAME> DEAN WITTER MID-CAP GROWTH FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> MAY-31-1996
<PERIOD-END> MAY-31-1996
<INVESTMENTS-AT-COST> 261,052,085
<INVESTMENTS-AT-VALUE> 304,346,869
<RECEIVABLES> 9,861,186
<ASSETS-OTHER> 117,289
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 314,325,344
<PAYABLE-FOR-SECURITIES> 4,212,683
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 840,950
<TOTAL-LIABILITIES> 5,053,633
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 238,479,393
<SHARES-COMMON-STOCK> 20,474,077
<SHARES-COMMON-PRIOR> 10,651,999
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 27,497,534
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 43,294,784
<NET-ASSETS> 309,271,711
<DIVIDEND-INCOME> 893,612
<INTEREST-INCOME> 1,056,112
<OTHER-INCOME> 0
<EXPENSES-NET> 4,012,243
<NET-INVESTMENT-INCOME> (2,062,519)
<REALIZED-GAINS-CURRENT> 45,084,990
<APPREC-INCREASE-CURRENT> 36,875,007
<NET-CHANGE-FROM-OPS> 79,897,478
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> (17,035,698)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 22,165,276
<NUMBER-OF-SHARES-REDEEMED> (13,590,922)
<SHARES-REINVESTED> 1,247,724
<NET-CHANGE-IN-ASSETS> 194,145,541
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 1,510,335
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 1,468,816
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 4,012,243
<AVERAGE-NET-ASSETS> 195,842,131
<PER-SHARE-NAV-BEGIN> 10.81
<PER-SHARE-NII> (0.10)
<PER-SHARE-GAIN-APPREC> 5.60
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> (1.20)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 15.11
<EXPENSE-RATIO> 2.05
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>