Kaitlin Cullum (born June 24, 1986 in Los Angeles, California) is an American actress.

She is best known for her role as Libby Kelly in the sitcom Grace Under Fire. Her other television credits include 7th Heaven, The Amanda Show, Malcolm in the Middle and had a brief recurring role in the sitcom 8 Simple Rules.

She also co-starred in the films A Little Princess, Galaxy Quest and the 2000 made-for-TV film Growing Up Brady, portraying Eve Plumb.

Sister of Kimberly Cullum.