Heizer (German for "fireman") is a German surname. Notable people with the surname include:
Ken Heizer (1924-2011), American football player Michael Heizer (born 1944), American artist Miles Heizer (born 1994), American actor Oscar S. Heizer (1868-1956), American diplomat Radomír Heizer (born 1987), Slovak ice hockey player Robert Heizer (1915-1979), American archaeologist
See also Heizer, Kansas, a community in the United States Der Heizer, a short story by Franz Kafka