WINTHROP
REALTY TRUST  FORM 10-Q MARCH 31, 2006

Exhibit 31.1

CERTIFICATION

I, Michael L.
Ashner, certify that:

| | 1. |  | I have reviewed this Quarterly Report on Form 10-Q of Winthrop Realty 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;
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| | 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 cash flows of the Registrant as of, and for, the  periods presented in
this report;
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| | 4. |  | The
Registrant's other certifying officer and I are responsible  for establishing and
maintaining disclosure controls and  procedures (as defined in Exchange Act Rules
13a-15(e) and  15d-15(e)) for the Registrant and have:
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| | (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;
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| | (b) |  | 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 the end of the  period covered by this report based on such evaluation;
and
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| | (c) |  | Disclosed in this report any changes in the Registrant's internal control
      over financial reporting that occurred during the Registrant's most recent
      fiscal quarter, that has materially affected, or is reasonably likely to
      materially affect, the Registrant's internal control over financial reporting;
      and
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| | 5. |  | The
Registrant's other certifying officer and I have disclosed,  based on our most recent
evaluation of internal control over  financial reporting, 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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WINTHROP
REALTY TRUST  FORM 10-Q MARCH 31, 2006

| | (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.
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|Date:
      May 10, 2006 | /s/ Michael L. Ashner  
|------------------------ | -----------------------
|                         |                        
|                         | Michael L. Ashner      
|                         | Chief Executive Officer

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