Júlio Afrânio Peixoto (December 17, 1876 – January 12, 1947) was a Brazilian physician, writer, politician, historian, university president, and pioneering eugenicist.
He held many public offices, including Brazilian congressional representative from Bahia in the federal Câmara de Deputados (federal congressman) (1924–1930), first the president of the Universidade Federal do Rio de Janeiro, member of the Brazil-United States Cultural Institute, president of the Academia Brasileira de Letras, and honorary doctorates from Coimbra University and the University of Lisbon, Portugal.