Pat O'Malley, nascut Patrick Henry O'Malley Jr. (Forest City, Pennsilvània, 3 de setembre de 1890 - Van Nuys, Califòrnia, 21 de maig de 1966), va ser un actor de teatre i vodevil nord-americà abans de començar una prolífica carrera cinematogràfica als setze anys. Més tard va fer carrera a la televisió.

Often confused with the British-born comic actor J. Pat O'Malley, who is the better remembered, silent dramatic film star Pat O'Malley had an enduring career that stands on its own. He was of solid Irish-American stock, born in Forest City, Pennsylvania, in 1890. A one-time railroad switchman, he also had circus experience by the time he discovered an interest in movie making. He began with the Kalem Studio in 1913 and appeared in a few Irish films before signing on with Thomas Edison's company in 1914. The following year, he married actress Lillian Wilkes, and three of their children, Eileen, Mary Katherine, and Sheila, would become actors as well. His brother Charles O'Malley was a sometime actor, appearing in westerns on occasion. His first identifiable film is The Alien (1913). He began freelancing in 1916 and from then on, appeared in scores of silents as both a rugged and romantic lead, some classic films being The Heart of Humanity (1918), My Wild Irish Rose (1922), and The Virginian (1923). He did not age well come sound pictures, and he was quickly relegated to supporting parts. He appeared in hundreds upon hundreds of bits (mostly unbilled) until 1956, when he retired. He died a decade later.