Torrey, John (1796–1873), a United States botanist and chemist. He described and classified hundreds of plants, including those collected by John C. Frémont and others on some 20 government expeditions to the West, 1820–58. Torrey influenced the careers of Asa Gray and a number of other botanists. He was professor of chemistry and natural history at the College of New Jersey (now Princeton), 1830–54, and professor of chemistry at the College of Physicians and Surgeons in New York City, 1827–55. Torrey was born in New York City and received an M.D. degree in 1818.

His major works were Flora of the State of New York (1843) and, with Asa Gray, Flora of North America (2 volumes, 1838–43).