Ensign is a surname. Notable people with the surname include:
Datus Ensign (1783–1853), Methodist minister and evangelist Harry Ensign (1883–1943), American cinematographer John Ensign (born 1958), American politician Margaret Ruth Ensign (1919–2017), American taxonomist Margee Ensign (born 1954), American academic administrator Michael Ensign (born 1944), American actor Tod Ensign (died 2014), American lawyer William L. Ensign (1928–2010), American architect