<DOCUMENT>
<TYPE>EX-99.77B
<SEQUENCE>3
<FILENAME>item-77b_12459.txt
<DESCRIPTION>ACCOUNTANT'S REPORT ON INTERNAL CONTROL
<TEXT>
               ITEM 77B - ACCOUNTANT'S REPORT ON INTERNAL CONTROL

Deloitte & Touche LLP
Two World Financial Center
New York, New York 10281-1414

                                                            Deloitte
                                                            & Touche
                                                             [LOGO]

Tel: (212) 436-2000
Fax: (212) 436-5000
www.us.deloitte.com


INDEPENDENT AUDITORS' REPORT


To the Board of Trustees and Shareholders of MassMutual Corporate
Investors and MassMutual Participation Investors (the "Trusts")

In planning and performing our audit of the consolidated financial statements of
the Trusts for the year ended December 31, 2003, (on which we have issued our
reports dated February 6, 2004), we considered the Trusts' internal control,
including control activities for safeguarding securities, in order to determine
our auditing procedures for the purpose of expressing an opinion on the
consolidated financial statements and to comply with the requirements of Form
N-SAR, not to provide assurance on the Trusts' internal control.

The management of the Trusts is responsible for establishing and maintaining
internal control. In fulfilling this responsibility, 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 consolidated financial statements for external
purposes that are fairly presented in conformity with accounting principles
generally accepted in the United States of America. Those controls include the
safeguarding of assets against unauthorized acquisition, use, or disposition.

Because of inherent limitations in any internal control, misstatements due to
error or fraud may occur and may not be detected. Also, projections of any
evaluation of internal control to future periods are subject to the risk that
internal control may become inadequate because of changes in conditions, or that
the degree of compliance with policies and procedures may deteriorate.

Our consideration of the Trusts' internal control would not necessarily disclose
all matters in the Trusts' 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 one or more of the internal control components does not reduce to a
relatively low level the risk that misstatements caused by error or fraud in
amounts that would be material in relation to the consolidated financial
statements being audited may occur and not be detected within a timely period by
employees in the normal course of performing their assigned functions. However,
we noted no matters involving the Trusts' internal control and its operation,
including controls for safeguarding securities, that we consider to be material
weaknesses as defined above as of December 31, 2003.

This report is intended solely for the information and use of the Trusts'
Management, the Board of Trustees and Shareholders of MassMutual Corporate
Investors and MassMutual Participation Investors, management and the Securities
and Exchange Commission and is not intended to be and should not be used by
anyone other than these specified parties.

/s/ Deloitte & Touche LLP
--------------------------------

February 6, 2004

-------------------
Deloitte
Touche
Tohmatsu
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