Mike O'Brien attended the University of Michigan, where he majored in film-video and was the founder and editor of a monthly comedy newspaper named The Anti-Daily. He graduated in 1999. He was a performer at iO Chicago and The Second City in Chicago. He trained at The Second City in Chicago, eventually joining the company's mainstage, where he performed for nearly 14 years. He co-created the web series "7 Minutes in Heaven with Mike O'Brien," where he awkwardly talks with someone in a closet for a few minutes and then tries to kiss them.

O'Brien auditioned for a spot as a cast member for both 2005 and 2009; the latter resulted in the writing job: he has been a writer since the 2009–10 season.

In August 2013, it was reported that O'Brien would join the cast for its 39th season. After one season on the show and with the hiring of stand-up comic Pete Davidson, O'Brien has been let go as a cast member, but will continue to be a show writer.

Comedians, Saturday Night Live (SNL), Writing, Television Writing, Comedy, Standup Comedy, Entertainment