The Wistar Institute is an independent, nonprofit research institution in biomedical science with special focuses in oncology, immunology, infectious disease and vaccine research. Located on Spruce Street in Philadelphia’s University City neighborhood, Wistar was founded in 1892 as a nonprofit institution to focus on biomedical research and training.

Caspar Wistar was an American physician and anatomist. He is sometimes referred to as Caspar Wistar the Younger, to distinguish him from his grandfather of the same name. The plant genus Wisteria is named for him.