Michael Sheen OBE (born 5 February 1969) is a BAFTA- and Laurence Olivier Award-nominated Welsh actor.

Having worked with screen writer Peter Morgan on five films, Sheen has become known for his portrayals of well-known public figures: Tony Blair in the Stephen Frears directed films The Deal and The Queen, David Frost in both the stage production and the film version of Frost/Nixon and football manager Brian Clough in The Damned United, among others. He is also known for his role as Lucian in the Underworld film series.

Michael Sheen was born in Newport, to Irene and Meyrick Sheen, both of whom worked in personnel management. His father is also a part-time professional Jack Nicholson look-alike. Michael has one sibling, a younger sister named Joanne.