Exhibit 99.CERT

                      CERTIFICATION PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002
                        ---------------------------------

I, Manfred Altstadt, Chairman of the Board, President and Chief Executive
Officer of Mutual of America Investment Corporation, certify that:

      1. I have reviewed this report on Form N-CSR of Mutual of America
Investment Corporation;

      2. Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

      3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and changes in net assets of the
registrant as of, and for, the periods presented in this report.

      4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Rule 30a-3(c) under the Investment Company Act of 1940) and internal control
over financial reporting (as defined in Rule 30a-3(d) under the Investment
Company Act of 1940) for the registrant and have:

            a)    Designed such disclosure controls and procedures, or caused
                  such disclosure controls and procedures to be designed under
                  our supervision, to ensure that material information relating
                  to the registrant, including its consolidated subsidiaries, is
                  made known to us by others within those entities, particularly
                  during the period in which this report is being prepared;

            b)    Designed such internal control over financial reporting, or
                  caused such internal control over financial reporting to be
                  designed under our supervision, to provide reasonable
                  assurance regarding the reliability of financial reporting and
                  the preparation of financial statements for external purposes
                  in accordance with generally accepted accounting principles;

            c)    Evaluated the effectiveness of the registrant's disclosure
                  controls and procedures and presented in this report our
                  conclusions about the effectiveness of the disclosure controls
                  and procedures, as of a date within 90 days prior to the
                  filing date of this report based on such evaluation; and




            d)    Disclosed in this report any change in the registrant's
                  internal control over financial reporting that occurred during
                  the second fiscal quarter of the period covered by this report
                  that has materially affected, or is reasonable likely to
                  materially affect, the registrant's internal control over
                  financial reporting; and

      5. The registrant's other certifying officer and I have disclosed to the
registrant's auditors and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):

            a)    All significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize, and report
                  financial information; and

            b)    Any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal control over financial reporting.

Date: February 28, 2005

                                        /s/ MANFRED ALTSTADT
                                        ----------------------------------------
                                        Manfred Altstadt,
                                        Chairman of the Board,
                                        President and Chief Executive Officer of
                                        Mutual of America Investment Corporation




                      CERTIFICATION PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002
                        ---------------------------------

I, John R. Greed, Executive Vice President, Chief Financial Officer and
Treasurer of Mutual of America Investment Corporation, certify that:

      1. I have reviewed this report on Form N-CSR of Mutual of America
Investment Corporation;

      2. Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

      3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and changes in net assets of the
registrant as of, and for, the periods presented in this report.

      4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Rule 30a-3(c) under the Investment Company Act of 1940) and internal control
over financial reporting (as defined in Rule 30a-3(d) under the Investment
Company Act of 1940) for the registrant and have:

            a)    Designed such disclosure controls and procedures, or caused
                  such disclosure controls and procedures to be designed under
                  our supervision, to ensure that material information relating
                  to the registrant, including its consolidated subsidiaries, is
                  made known to us by others within those entities, particularly
                  during the period in which this report is being prepared;

            b)    Designed such internal control over financial reporting, or
                  caused such internal control over financial reporting to be
                  designed under our supervision, to provide reasonable
                  assurance regarding the reliability of financial reporting and
                  the preparation of financial statements for external purposes
                  in accordance with generally accepted accounting principles;

            c)    Evaluated the effectiveness of the registrant's disclosure
                  controls and procedures and presented in this report our
                  conclusions about the effectiveness of the disclosure controls
                  and procedures, as of a date within 90 days prior to the
                  filing date of this report based on such evaluation; and

            d)    Disclosed in this report any change in the registrant's
                  internal control over financial reporting that occurred during
                  the second fiscal quarter of the period covered by this




                  report that has materially affected, or is reasonable likely
                  to materially affect, the registrant's internal control over
                  financial reporting; and

      5. The registrant's other certifying officer and I have disclosed to the
registrant's auditors and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):

            a)    All significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize, and report
                  financial information; and

            b)    Any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal control over financial reporting.

Date: February 28, 2005

                                        /s/ JOHN R. GREED
                                        ----------------------------------------
                                        John R. Greed,
                                        Executive Vice President,
                                        Chief Financial Officer and Treasurer of
                                        Mutual of America Investment Corporation