High Quality Content by WIKIPEDIA articles! Daniel Louis "Dan" Castellaneta (born October 29, 1957) is an American actor, voice actor, comedian, singer and screenwriter. Noted for his long-running role as Homer Simpson on the animated television series The Simpsons, he voices many other characters on The Simpsons, including Abraham "Grampa" Simpson, Barney Gumble, Krusty the Clown, Groundskeeper Willie, Mayor Quimby and Hans Moleman.