The German/Irish actor began dating Beharie after they shared a steamy bedroom scene in the 2011 film, in which he played a man struggling with sex addiction.
However, Beharie has now confirmed she and Fassbender have decided to go their separate ways.
In a post on her Twitter.com page, she wrote: "Yes it's true Fassbender and I are no longer dating."
Fassbender went public with their romance last year, but admitted geography sometimes hampered the relationship.
He said: "We're trying to see each other as often as possible. That's kind of difficult when she lives here (in New York) and I live in England."