No successor had been named for Kaminski, who will leave the newspaper May 25 to open a media and management services company.
Kaminski, 54, began at The Repository as an editorial assistant in 1974 and was a reporter, designer, news editor and managing editor before being named editor in 1997. He is a former president of the Associated Press Society of Ohio.
Publisher David J. Greenfield also is leaving The Repository, retiring on Friday. GateHouse Media Inc. purchased the newspaper this year from Copley Press Inc.
The Repository has an average weekday circulation of 64,139 and Sunday circulation of 82,363.
By: Dave Kaminski, editor of The Repository, announced his resignation Tuesday after 33 years with the newspaper.