His first feature film role was in the 1982 comedy film Hanky Panky with Gene Wilder and Gilda Radner. He also appeared in Carl Reiner's 1987 comedy Summer School and Martin Scorsese's hit 1990 crime drama Goodfellas as Henry Hill's father. His most recent role is in the 2005 hit movie Cinderella Man. Starr made many guest appearances on television series, including T.J. Hooker, The A-Team, Knight Rider, Hill Street Blues, V: The Series, The 4400, A Nero Wolfe Mystery and NYPD Blue.
Starr was born in Queens, New York, to a Retail employee mother and a meatpacker father. His brother is actor Mike Starr. Beau Starr's well-known television role was in the 1990s Canadian television series Due South as Lieutenant Harding Welsh of the Chicago Police Department. He also starred in the 1980s television series Rituals, Bizarre and True Blue. He has starred in several made-for-television movies, and appeared in a number of productions based in Canada, including Due South, Sue Thomas: F.B.Eye and Doc as well as some advertisements.