Whose Line is it Anyway? (often known as simply Whose Line?) is an improvisational comedy show, which was originally hosted by Drew Carey on ABC and ABC Family and ran from August 5, 1998 to December 15, 2007. Repeats and previously unaired episodes were subsequently run on ABC Family from 2005 to 2011. The show was later revived in 2013, hosted by Aisha Tyler and airing on The CW, with the first episode of the revival airing on July 16, 2013.

The series is a spin-off of the British show of the same name. The three primary performers, Ryan Stiles, Wayne Brady, and Colin Mochrie, who had also appeared on the original UK show, are joined by a recurring cast member or a special guest as the fourth performer.