Donny Most (born August 8, 1953 in Brooklyn, New York, USA) is an American actor best known for his role as Ralph Malph on the long-running television series Happy Days. He is also known for his voice roles on several Saturday morning cartoon series. Among them, Ralph Malph on Fonz and the Happy Days Gang (1980); Eric the Cavelier in Dungeons & Dragons (1983); and Stiles on Teen Wolf (1986-1989).
Film credits include Edtv (1999) and most recently, Planting Melvin (2005). He also made guest appearances on many TV shows, including CHiPs, the Love Boat, Sliders, and Star Trek: Voyager.
Don Most is married to actress Morgan Hart.
He is sometimes credited as Donny Most.