Martin McCann grew up with a brother and sister in the Divis Flats area on the Falls Road in Belfast.

In 2006, Lord Richard Attenborough invited McCann to appear in his film after seeing him as Alex in a stage production of "A Clockwork Orange." Attenborough called Spielberg and recommended McCann. He was invited to Los Angeles to audition for the HBO miniseries "The Pacific"; Attenborough sent Spielberg scenes from his film to watch. McCann won the role of R. V. Burgin in "The Pacific."

In early 2010, he was filming in Belfast in a new musical comedy, "Killing Bono," a film about the life of one of Bono's schoolmates, who tries to make it in the music business, but whose failures and frustrations are heightened against the backdrop of U2's continuing rise. McCann plays the role of Bono. He has performed on stage in Ireland and on tours.

In 2011, Martin received the Irish Film and Television Award for Best Actor in a Feature Film; the nominees in that category included his fellow Northern Irishman Liam Neeson, Cillian Murphy, and Colm Meaney.