Exhibit 31.1

				CERTIFICATION



I, Michael A. Winner, certify that:

     1.  I have reviewed this quarterly report on Form 10-Q of Ohio Casualty
	 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 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 Exchange Act Rules 13a-15(e) and 15d-15(e)) and
	 internal control over financial reporting (as defined in exchange
	 Act Rules 13a-15(f)) 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 the
		end of the period covered by 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 registrant's most recent fiscal quarter (the
		registrant's fourth fiscal quarter in the case of an
		annual 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,
	 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):

	    (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:  April 25, 2005                        /s/Michael A. Winner
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					     Michael A. Winner
					     Executive Vice President and
					     Chief Financial Officer