Garretson is a surname and patronymic name meaning "son of Garret". Notable people with the surname include:
Austin B. Garretson (1856–1931), an American labor leader who became president of the Order of Railway Conductors. Bob Garretson (1933–2025), American racing driver Darell Garretson (1932–2008), American basketball referee John Wesley Garretson (1812-1895), a surveyor who mapped large areas of Askansas and New Mexico Katy Garretson, American television director Mary Welleck Garretson (1896–1971), American geologist and paleontologist Ron Garretson (born 1958), American professional basketball referee A. S. Garretson Founder of Garretson, South Dakota and Corona, California
See also Garretson House (disambiguation), historic houses