Forstmann is a German surname. Notable people with the surname include:
Arnold Forstmann (1842–1914), German artist Gustav Forstmann (1908–1985), German naval commander Judith Forstmann (died 2009), Argentinian politician Julius Anthony (Tony) Forstmann, businessman Nicholas C. Forstmann (1947–2001), businessman Theodore J. Forstmann (1940–2011), businessman Walther Forstmann (1883–1973), German U-boat commander
See also Forstmann Little & Company ForstmannLeff (founded 1968), founded by J. Anthony Forstmann and Joel B. Leff Förstemann