Dear Ruth is a 1947 American romantic comedy film starring Joan Caulfield, William Holden, Mona Freeman, Billy De Wolfe and Edward Arnold. It was based on the 1944 Broadway play of the same name by Norman Krasna.

The film's plot concerns a teenage girl who uses her older sister's identity to communicate with a soldier pen pal.

Two sequels to Dear Ruth were later produced: Dear Wife (1949), with all of the principal actors reprising their roles, and Dear Brat (1951), featuring Freeman, Arnold and De Wolfe.

Despite the popular belief that J. D. Salinger based the name of his character Holden Caulfield, who appears in The Catcher in the Rye and other works, on a marquee for the film showing the last names of the film's two leads, the first Holden Caulfield story, "I'm Crazy", was published in December 1945, a year and a half before the film's release.