Michael was born in Roman Catholic family of Civil Engineer father, George Douglas and housewife mother, Leona Elizabeth. Michael was the youngest of all the seven children they had. Michael went to Montour High School located in Pennsylvania. He then attended speech course in the Kent state for around 2 years but left it and shifted to Pittsburgh.
Michael started his acting career with the film Rabbit Test in 1978. Four years later he starred in a film titled Night Shift in 1982. His comedic role was well praised and thereafter he did similar roles in several films like Mr. Mom, Beetlejuice, Batman and Batman Retuens among several others. Keaton then shifted into different genre of films like thriller, romanctic comedy and action. Some of his well-known movies are The Dream Team, Need For Speed, Birdman and Spotlight among several others.
On personal front Kate married former Actress Caroline McWilliams in 1982, but the marriage couldn’t last long and the couple finally divorced in 1990. The couple was blessed with a son Sean Douglas. After his marriage got over he was in relationship with Actress Courteney Cox for few years.