Olsen, 25, and Holbrook, 33, first started dating in 2012 after they met on the set of their film 'Very Good Girls', co-starring Dakota Fanning and Demi Moore, reported Us magazine.
Their broken engagement news comes after Olsen was photographed this past weekend at a farmer's market in Studio City, California, without her engagement ring.
The duo got engaged last March, less than two weeks after her big sister Mary-Kate Olsen was set to marry financier Olivier Sarkozy.