Grantham is an English surname which has been spread to North America and Australasia. Notable people with the surname include:
Alexander Grantham (1899–1978), British colonial administratorDonald Grantham, American composerSir Guy Grantham, (1900–92) British Admiral, Commander-in-Chief at PortsmouthJeremy Grantham, Chairman of the Board of Grantham Mayo Van Otterloo, a Boston-based asset management firmJoseph Grantham (died 1830), first police officer to be killed on duty in the United KingdomLeslie Grantham, British TV actorRoy Grantham (1926–2013), British trade union leaderSir Thomas Grantham, commander of the naval fleet of the British East India CompanyWilliam Grantham (1835–1911), English judge and Conservative M.P. for East Surrey and Croydon