Geis is a German surname. Notable people with the surname include:
George J. Geis (c.1860–1936), American Baptist minister and anthropologist
Gerald Geis (born 1933), American politician
Irving Geis (1908–1997), American artist
Jacob Geis (1890–1972), German theatre director, screenwriter and film producer
Johannes Geis (born 1993), German footballer
Norbert Geis (born 1939), German politician
Richard E. Geis (1927–2013), American science fiction fan and writer
