<PAGE> PAGE 1
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013 B010001 SPRINGFIELD
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<PAGE> PAGE 2
015 C010001 BROOKLYN
015 C020001 NY
015 C030001 11245
015 E010001 X
018 000000 Y
019 A000000 Y
019 B000000 32
019 C000000 MASSMUTUAL
020 A000001 JONES & ASSOCIATES, INC.
020 B000001 95-3583143
020 C000001 8
020 A000002 LEGG MASSON WOOD WALKER
020 B000002 52-0902557
020 C000002 6
020 A000003 DONALDSON, LUFKIN & JENRETTE
020 B000003 13-2741729
020 C000003 5
020 A000004 ALLEN & COMPANY INCORPORATED
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020 C000004 2
020 A000005 ADVEST INSTITUTE SERVICES
020 B000005 06-0950348
020 C000005 1
020 A000006 MERRILL LYNCH, PIERCE, FENNER & SMITH, INC.
020 B000006 13-5674085
020 C000006 1
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020 B000007 13-3179859
020 C000007 1
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022 C000002 43725
022 D000002 3065
022 A000003 MORGAN (J.P.) SECURITIES INC.
022 B000003 13-3224016
022 C000003 22844
022 D000003 649
022 A000004 LEHMAN BROTHERS INC.
022 B000004 13-2518466
022 C000004 20769
022 D000004 2438
<PAGE> PAGE 3
022 A000005 DONALDSON, LUFKIN & JENRETTE SECURITIES CORP.
022 B000005 13-2741729
022 C000005 5861
022 D000005 3755
022 A000006 JEFFERIES & CO
022 B000006 45-2622900
022 C000006 5967
022 D000006 3320
022 A000007 MORGAN, STANLEY & CO., INCORPORATED
022 B000007 13-2655998
022 C000007 5129
022 D000007 2896
022 A000008 GRANTCHESTER SECURITIES INC.
022 B000008 13-3502273
022 C000008 2229
022 D000008 3259
022 A000009 CHASE SECURITIES INC.
022 B000009 13-3112953
022 C000009 3998
022 D000009 1385
022 A000010 BT SECURITIES
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<PAGE> PAGE 4
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<PAGE> PAGE 5
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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<PAGE> PAGE 8
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<PAGE> PAGE 9
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SIGNATURE STEPHEN L. KUHN
TITLE SECRETARY
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
REPORT TO SHAREHOLDERS OF MASSMUTUAL PARTICIPATION INVESTORS FOR THE YEAR
ENDED DECEMBER 31, 1997 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000831655
<NAME> MASSMUTUAL PARTICIPATION INVESTORS
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1997
<PERIOD-START> JAN-01-1997
<PERIOD-END> DEC-31-1997
<INVESTMENTS-AT-COST> 127,879,126
<INVESTMENTS-AT-VALUE> 134,944,220
<RECEIVABLES> 2,474,686
<ASSETS-OTHER> 62,841
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 137,481,747
<PAYABLE-FOR-SECURITIES> 100,000
<SENIOR-LONG-TERM-DEBT> 22,500,000
<OTHER-ITEMS-LIABILITIES> 8,726,162
<TOTAL-LIABILITIES> 31,326,162
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 84,895,820
<SHARES-COMMON-STOCK> 9,216,665
<SHARES-COMMON-PRIOR> 9,216,665
<ACCUMULATED-NII-CURRENT> 402,704
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 8,276,291
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 7,065,094
<NET-ASSETS> 106,155,585
<DIVIDEND-INCOME> 292,721
<INTEREST-INCOME> 9,882,497
<OTHER-INCOME> 0
<EXPENSES-NET> 2,161,910
<NET-INVESTMENT-INCOME> 8,013,308
<REALIZED-GAINS-CURRENT> 10,021,006
<APPREC-INCREASE-CURRENT> 368,411
<NET-CHANGE-FROM-OPS> 18,402,725
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 7,617,829
<DISTRIBUTIONS-OF-GAINS> 1,783,170
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 9,040,726
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 5,423,509
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 964,592
<INTEREST-EXPENSE> 983,508
<GROSS-EXPENSE> 2,161,910
<AVERAGE-NET-ASSETS> 105,537,352
<PER-SHARE-NAV-BEGIN> 10.54
<PER-SHARE-NII> 0.87
<PER-SHARE-GAIN-APPREC> 1.13
<PER-SHARE-DIVIDEND> 0.83
<PER-SHARE-DISTRIBUTIONS> 0.19
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 11.52
<EXPENSE-RATIO> 0.205
<AVG-DEBT-OUTSTANDING> 14,576,923
<AVG-DEBT-PER-SHARE> 1.58
</TABLE>
EXHIBIT INDEX TO FORM N-SAR
OF MASSMUTUAL PARTICIPATION INVESTORS
FOR THE PERIOD ENDED DECEMBER 31, 1997
Exhibit No. Description
77B. Accountant's Report on Internal Control
Coopers Coopers & Lybrand L.L.P.
& Lybrand a professional services firm
To the Board of Trustees of
MassMutual Participation Investors:
In planning and performing our audit of the financial statements of MassMutual
Participation Investors for the year ended December 31, 1997, we considered its
internal control, including controls over safeguarding securities, in order to
determine our auditing procedures for the purpose of expressing our opinion on
the financial statements and to comply with the requirements of Form N-SAR, not
to provide assurance on internal control.
The management of MassMutual Participation Investors is responsible for
establishing and maintaining internal control. In fulfilling this respon-
sibility, estimates and judgments by management are required to assess the
expected benefits and related costs of controls. Generally, controls that
are relevant to an audit pertain to the entity's objective of preparing
financial statements for external purposes that are fairly presented in
conformity with generally accepted accounting principles. Those controls
include safeguarding of assets against unauthorized acquisition, use or
disposition.
Because of inherent limitations in internal control, errors or irregularities
may occur and may not be detected. Also, projection of any evaluation of
internal control to future periods is subject to the risk that it may become
inadequate because of changes in conditions or that the effectiveness of the
design and operation may deteriorate.
Our consideration of internal control would not necessarily disclose all
matters in internal control that might be material weaknesses under standards
established by the American Institute of Certified Public Accountants.
A material weakness is a condition in which the design or operation of any
specific internal control component does not reduce to a relatively low level
the risk that errors or irregularities in amounts that would be material in
relation to the financial statements being audited may occur and not be
detected in a timely period by employees in the normal course of performing
their assigned functions. However, we noted no matters involving internal
control, including controls over safeguarding securities, that we consider
to be material weaknesses as defined above as of December 31, 1997.
This report is intended solely for the information and use of management and
the Securities and Exchange Commission.
Coopers & Lybrand L.L.P.
Springfield, Massachusetts
January 30, 1998
Coopers & Lybrand L.L.P. is a member of Coopers & Lybrand International,
a Swiss limited liability association.
