Grinham is a surname. Notable people with the surname include:
James Grinham (christened 20 December 1798-death unknown), English amateur cricketer Jodie Grinham (born 1993), British archer Judy Grinham (born 1939), British competitive swimmer Natalie Grinham (born 1978), Australian squash player Rachael Grinham (born 1977), Australian squash player