Billy Sullivan (1900s catcher)

William "Billy" Sullivan (born August 12, 1875, in Chicago, Illinois; died December 22, 1965, in Chicago, Illinois) was a professional baseball catcher who played in Major League Baseball from 1899 to 1909. He played for the Chicago White Sox, Boston Americans (later Red Sox), and Chicago Cubs. Sullivan's primary years were spent with the White Sox, where he was a key member of their 1906 World Series championship team, defeating the heavily favored Chicago Cubs.

Sullivan was known for his defensive prowess and was considered one of the better catchers of his era. He was also a capable hitter, particularly adept at getting on base. After his playing career, he remained involved in baseball, working as a scout and coach. His brother, Danny Sullivan, was also a major league catcher. Sullivan also served as an umpire in the American League for a brief period in 1913.