Ann Hawkins Gentry (January 21, 1791 - January 18, 1870) was the second woman in the United States to become a postmistress as well as a leading pioneer in Columbia, Missouri. She was the wife of American politician and military officer Richard Gentry who became Columbia's first mayor. Thomas Hart Benton helped her secure her historic appointment as postmistress after her husband died in 1837 fighting in the Second Seminole War. Her husband had been Columbia's second postmaster, running it from one corner of their tavern. Ann Gentry served as postmistress from 1838 until 1865.