The Critics' Choice Movie Award for Best Supporting Actor is one of the awards given by the Broadcast Film Critics Association at their annual Critics' Choice Movie Awards for a performance in a motion picture. It was first presented in 1995 with the winners being a tie between Ed Harris for Apollo 13 and Kevin Spacey for The Usual Suspects. There were no official nominees until 2001, currently six nominees are usually presented.

Mahershala Ali is the only actor who has received this award more than once, with two wins. Mark Ruffalo holds the record of most nominations in the category with four.