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                                                              Exhibit EX-99.CERT

                                 CERTIFICATIONS

I, W. Douglas Beck, President of UBS Managed Municipal Trust, certify that:

1.   I have reviewed this report on Form N-CSR of UBS Managed Municipal Trust;

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, changes in net
     assets, and cash flows (if the financial statements are required to include
     a statement of cash flows) of the registrant as of, and for, the periods
     presented in this report;

4.   The registrant's other certifying officer(s) 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 reasonably likely to materially
               affect, the registrant's internal control over financial
               reporting; and

5.   The registrant's other certifying officer(s) 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):

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          (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.


By: /s/ W. Douglas Beck
    ---------------------------------
    W. Douglas Beck
    President

Date: September 8, 2006

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I, Thomas Disbrow, Vice President and Treasurer of UBS Managed Municipal Trust,
certify that:

1.   I have reviewed this report on Form N-CSR of UBS Managed Municipal Trust;

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, changes in net
     assets, and cash flows (if the financial statements are required to include
     a statement of cash flows) of the registrant as of, and for, the periods
     presented in this report;

4.   The registrant's other certifying officer(s) 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

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               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 reasonably likely to materially
               affect, the registrant's internal control over financial
               reporting; and

5.   The registrant's other certifying officer(s) 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.


By: /s/ Thomas Disbrow
    ---------------------------------
    Thomas Disbrow
    Vice President and Treasurer

Date: September 8, 2006