The Torrey Botanical Society is an organization of people interested in plant life, including professional and amateur botanists, students, and those who just like to go out into the country and study nature. The society began informally in the 1860's under the aegis and inspiration of Dr. John Torrey, then professor of botany at Columbia College, and claims to be the oldest botanical society in America. The early members were amateur botanists and some students and colleagues of Dr. Torrey, who were interested in collecting and identifying plants. They occasionally met in the evening to discuss their findings. The organization was first named with the appearance of its first publication, The Bulletin of the Torrey Botanical Society, in 1870, and was incorporated in 1873.

Today, the society holds as its objectives "to promote interest in botany, and to collect and disseminate information on all phases of plant science." These objectives are fulfilled through indoor meetings, outdoor meetings or fields trips, and publications. Because the publications have become standard reference material for botanists, many people residing in practically every state and in a number of other countries have become members, primarily to receive the publications. Thus, the society has become an international organization and is affiliated with the American Institute of Biological Sciences. It differs from most scientific societies in the numerous meetings and field trips.