He had a long career in theater before making movies, playing hundreds of roles, mostly rustic bumpkins, in stage and stock. His film career included two isolated early films: White Woman (1933) and Soak the Rich (1936). It began in earnest with the part of Orion Peabody in the Spencer Tracy-Katharine Hepburn wartime drama Keeper of the Flame (1942); Kilbride was already fifty-four by then. The movie public really came to recognize him when he played the part of Pa Kettle (against Marjorie Main's Ma) in The Egg and I (1947), a role he reprised for seven more "Ma and Pa Kettle" movies, the last of which, and the last of his career, was in 1955.