Harry Allen (July 10, 1883 – December 4, 1951) was an Australian-born American character actor of the silent and sound film eras.

He began his acting career on stage with the J. C. Williamson organisation, performing around Australia. In 1910 he married fellow actor Marjorie Josephine née Condon in Brisbane. The union was not a success and in 1912 he left Australia for North America. In the United States, Allen was a member of a touring theater company, known for their popular rendition of The Better 'Ole. He appeared on Broadway in the early 1920s.

His first film role was in the 1923 silent film, The Last Moment, in a supporting role. In his career Allen appeared in over 100 films, mostly in supporting and smaller roles. Some of the more notable films he appeared in include: Of Human Bondage (1934), starring Bette Davis and Leslie Howard; the Marx Brothers' classic, A Night at the Opera; the original Mutiny on the Bounty (1935), starring Charles Laughton and Clark Gable; William Wyler's 1942 Academy Award-winning film, Mrs. Miniver, starring Greer Garson, Walter Pidgeon, and Teresa Wright; Jane Eyre (1944), starring Orson Welles and Joan Fontaine; the Mickey Rooney and Elizabeth Taylor version of National Velvet (1945); and The Picture of Dorian Gray (1945), starring George Sanders. His final appearance on film was in the 1949 film, Challenge to Lassie, starring Edmund Gwenn.

Allen died on December 4, 1951, and was buried in Glen Abbey Memorial Park.