Cullinan is a surname. Notable people with the surname include:
Alphonsus Cullinan (born 1959), Irish bishop Cormac Cullinan (fl. 1990s-present), South African attorney and author Daryll Cullinan (born 1967), South African cricketer Edward Cullinan (1931–2019), British architect Joseph S. Cullinan (1860–1937), American oil industrialist Mark Cullinan (born 1957), South African cricketer Mary Cullinan (1950–2021), American university president Patrick Cullinan (1932–2011), South African writer Shane Cullinan (born 1975), British composer Thomas Cullinan (diamond magnate), (1862–1936), South African diamond magnate Thomas A. Cullinan (1838–1904), US law enforcement officer