PAGE  1
000 B000000 12/31/2008
000 C000000 0000275694
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 Y
000 H000000 N
000 I000000 6.1
000 J000000 U
001 A000000 MASSMUTUAL CORPORATE INVESTORS
001 B000000 811-2183
001 C000000 4132261516
002 A000000 1500 MAIN STREET, P.O. BOX 15189
002 B000000 SPRINGFIELD
002 C000000 MA
002 D010000 01115
002 D020000 5189
003  000000 N
004  000000 N
005  000000 N
006  000000 N
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058 A000000 N
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062 R000000  18.4
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      PAGE  2
074 N000000   244311
074 T000000   208144
074 U010000     9320
075 A000000        0
075 B000000   238245
077 A000000 Y
080 A000000 NATIONAL UNION FIRE INSURANCE COMPANY
080 B000000 NONE
080 C000000     1125
081 A000000 Y
081 B000000   1
082 A000000 N
082 B000000        0
083 A000000 N
083 B000000        0
084 A000000 N
084 B000000        0
085 A000000 Y
085 B000000 N
SIGNATURE   JAMES M. ROY
TITLE       V.P. AND C.F.O.