Matthew Cowles (born 28 September 1944) is a US actor and playwright.
In 1966 Cowles played the title role in Edward Albee's short-lived adaptation of James Purdy's comic novel Malcolm on Broadway at the Shubert Theatre.
His first television part was Joe Czernak in the series NYPD in 1969. He was nominated for an Daytime Emmy as Outstanding Actor in a Daytime Drama Series in 1978 and won Outstanding Supporting Actor in a Daytime Drama Series in 1981 for his part as Billy Clyde Tuggle in All My Children, a role that he created and wrote.
The first film in which he performed was the comedy drama Me, Natalie (1969) in which he played Harvey Belman. Al Pacino also made his debut in this film.
Most recently Cowles appeared as Cowboy Dan in the television show Life on Mars.