Kyle Richard Gass (born July 14, 1960) is an American musician and actor best known for being a member of Tenacious D, winner of a Grammy Award for Best Metal Performance, alongside longtime friend Jack Black. He also co-formed, and performs with, the bands Trainwreck and Kyle Gass Band. Outside of music, Gass makes sporadic appearances as an actor; his appearances include the films Elf and Kung Fu Panda, TV shows such as Friends and Seinfeld and various music videos for bands such as Good Charlotte and I Prevail. He hosted a YouTube channel from 2009 to 2012 called Guitarings alongside fellow Tenacious D guitarist John Konesky.
Kyle Gass was born in Walnut Creek, California, and has two brothers. He attended Las Lomas High School, where he played flute in the marching band, and preceded G. Williams, graduating in 1978. He has suffered from male pattern baldness since he was a child. He studied acting at UCLA School of Theater, Film and Television, where he met Tim Robbins. In 1982, he joined Robbins' The Actors' Gang and in the early 1990s met and befriended Jack Black in the group.