Karen Kilgariff (born May 11, 1970 in Petaluma, California) is an actress and writer best known for her work on the late 1990s sketch comedy television program Mr. Show and the Glasgow-set situation comedy The Book Group. She is currently the head writer for The Ellen DeGeneres Show and occasionally appears on screen in sketches and other segments.

Began her stand-up career in Sacramento, California in 1990. Since then she has played clubs and colleges all over the country and appeared in numerous stand-up specials. She has also been a featured actor in sitcoms, sketch shows and theatre productions in Los Angeles since 1995.