No reason was given for the split of the former "Midnight in Paris" co-stars.
McAdams, 34, and Sheen, 44, met on the set of the film, remained friends throughout production and began attending public events together as a couple in October 2010.
The actress previously was engaged to her "Notebook" leading man Ryan Gosling.
Sheen has a 14-year-old daughter with his ex-girlfriend, actress Kate Beckinsale.
DISCUSS AND COMMENT ON THIS STORY Reality TV World now offers Facebook Comments on our stories. To post a comment, log into Facebook and then 'Add' your comment. To report spam or abuse, click the 'X' in the upper right corner of the comment box.