Hemmer is a surname. Notable people with the surname include:
Bill Hemmer (born 1964), American television news anchorFrank Hemmer (born 1963), West German-German slalom canoeistGerardo Hemmer (1971–1995), Mexican actorHans Ritter von Hemmer, (1869–1931), officer in the Royal Bavarian Army, Knight Commander of the Military Order of Max JosephJarl Hemmer (1893–1944), Finland-Swedish author from Vaasa, FinlandMari Hemmer (born 1983), Norwegian long-track speedskaterMartin Hemmer, German slalom canoeist who competed in the early 1990sRafael Lozano-Hemmer (born 1967), Mexican-Canadian electronic artist