Ralph Dunn was an American film, television, and stage actor.

Dunn was born in Titusville, Pennsylvania and spent early years living with relatives in Canton, Illinois. Dunn's father was a veterinarian for the U.S. Army during WWI, and his mother was an actress. Dunn was enrolled briefly at the University of Pennsylvania, but left after one day to join a Vaudeville troupe.

Ralph Dunn used his burly body and rich, theatrical voice to good effect in hundreds of minor feature-film roles and supporting appearances in two-reel comedies. He came to Hollywood during the early talkie era, beginning his film career with 1932's The Crowd Roars.

A large man with a withering glare, Dunn was an ideal "opposite" for short, bumbling comedians. A frequent visitor to the Columbia short subjects unit, Dunn showed up in the Three Stooges comedies Mummy's Dummies, as well as Who Done It? and its remake, For Crimin' Out Loud

Dunn kept busy into the 1960s, appearing in such TV series as Kitty Foyle, and Norby and such films as Black Like Me.