The network ordered 10 episodes of the new series, and production will begin next year.
The 44-year-old actor and 46-year-old comedian co-created and wrote the sitcom, and Galifianakis will star as Chip Baskets. The character is determined to become a professional clown, but is rejected from a prestigious clown school and lands a stint at a rodeo. Saturday Night Live and Portlandia screenwriter Jonathan Krisel will serve as showrunner.
"Zach Galifianakis, Louis C.K. and Jonathan Krisel have created an absolutely brilliant show," FX original programming president Eric Schrier said in a statement. "To say Zach's portrayal of the lead character Chip Baskets is hilarious/unique/riveting/fascinating would be an understatement. We can't wait for the world to meet him."
Baskets is expected to premiere on FX in 2016. Galifianakis will appear in Birdman in October, and Louis C.K. series Louie will return for a fifth season on FX in 2015.