Sizemore is a family name. Notable people with the surname include:
Barbara Sizemore (1927–2004), American educator and researcher Bill Sizemore (born 1951), American political activist Chris Costner Sizemore (1927–2016), American patient with multiple personality disorder Grady Sizemore III (born 1982), American professional baseball player Herschel Sizemore (1935–2022), American mandolinist James Sizemore (born 1978), American composer and orchestrator of film scores Jason Sizemore, American writer and editor Scott Sizemore (born 1985), American professional baseball player Susan Sizemore (1951–2020), American novelist Ted Sizemore (born 1945), American former professional baseball player Tom Sizemore (1961–2023), American actor
See also Roy Sizmore (born 1950), English former motorcycle speedway rider and Grasstrack rider