The American Physiological Society is a non-profit professional society for physiologists. It has nearly 10,000 members, most of whom hold doctoral degrees in medicine, physiology, or other health professions. Its mission is to support research and education in the physiological sciences. The society publishes 16 peer-reviewed journals, sponsors scientific conferences, and sponsors awards to further this mission.

Since it was founded in 1887, APS has had many notable scientists lead the organization, beginning with founder Henry Bowditch and continuing through its current president. APS is governed by an elected Board of Directors. The Board includes a president, immediate past president and president-elect, each serving a one-year term. Management of the affairs of the society is the responsibility of a full-time chief executive officer, who serves as secretary of the board. The society maintains a staff and offices in Rockville, Maryland.

The American Physiological Society was founded in 1887 with 28 members. Of them, 21 were graduates of medical schools, but only 12 had studied in institutions with a physiology professor.

The American Physiological Society was founded at a time when very few physiological laboratories existed in the United States and there were few investigators. The newly established society was one of the earliest national disciplinary societies in the sciences, the first society in the biomedical sciences, and likely the first to require its members to publish original research. The stated object of the society was to promote the advancement of physiology and to facilitate discourse among American physiologists. There was a conscious effort to ensure the representation of all areas within physiology, encompassing topics as diverse as neurology, psychology, ophthalmology, pathology and therapeutics, as well as plant physiology and animal biology.

The APS recognizes five physiologists as its founders: Henry Pickering Bowditch, Silas Weir Mitchell, and Henry Newell Martin co-signed the original letter to active physiology researchers inviting them to the new society, and John Green Curtis and Russell Henry Chittenden provided early organizational support. The organizational meeting founding the society was held on December 30, 1887, in Curtis' laboratory space at Columbia University and was attended by seventeen people. The society had 28 founding members. The first regular meeting of the APS followed in September 1888 in Washington, DC, featuring paper presentations and demonstrations.

In its early days the APS served a young field with relatively few dedicated researchers, so its efforts were oriented toward advancing teaching and research. APS members collaborated to author a textbook of physiology and launched a journal, the American Journal of Physiology, in 1898. As the field of physiology matured, the society expanded in membership.

The modern APS sponsors many awards, including the Horace W. Davenport Distinguished Lecturer, the Walter B. Cannon Award, and Arthur C. Guyton Award, and the Henry Pickering Bowditch Award.

The American Physiological Society publishes peer-reviewed journals and books as a nonprofit publisher.