William "Billy" Sweetzer (born 15 February 1958) is a Canadian former professional soccer player.
He began his career in England as a youth player with both Oxford United and Queens Park Rangers, before he became a professional with Brentford – although he never made a league appearance.
He later played non-league football with Bracknell Town, before playing in the NASL for the Tampa Bay Rowdies in 1981.
His brothers Gordon and Jimmy also played professional soccer.