William Castle (disambiguation)

William Castle may refer to:

• William Castle (1914–1977), American film director, producer, and actor
• William B. Castle (1814–1872), American politician from Ohio
• William Bosworth Castle (1897–1990), American physician and physiologist
• William Ernest Castle (1867–1962), American geneticist
• William Richards Castle (1849–1935), lawyer, politician and Attorney General of Hawaii
• William Richards Castle, Jr. (1878–1963), U.S. educator, diplomat and ambassador to Japan