Steinmetz is a German surname, meaning stonemason
- People named Steinmetz
- Johann Adam Steinmetz (1689–1762), German Lutheran theologian
- Karl Friedrich von Steinmetz (1796–1877), Prussian field marshal
- Charles Proteus Steinmetz (1865–1923), German-American mathematician and electrical engineer
- Charles P. Steinmetz Academic Centre (Steinmetz High School, Chicago, IL), named for the mathematician and electrical engineer
- Steinmetz circuit (de:Steinmetzschaltung), a method to use three phase motors with single phase AC, invented by Charles Proteus Steinmetz
- Steinmetz solid in geometry, the solid body generated by the intersection of two or three cylinders of equal radius at right angles, named after Charles Proteus Steinmetz
- IEEE Charles Proteus Steinmetz Award
- Barnabás Steinmetz (born 1975), Hungarian water polo player
- Christian Steinmetz (1882–1963), American collegiate basketball player
- Chris Steinmetz (born 1966), American record producer and engineer
- David Steinmetz, American historian
- Donald W. Steinmetz (born 1924), American former member of the Wisconsin Supreme Court
- Francis Steinmetz (1914–2006), Dutch officer who escaped from Colditz Castle
- Klement Steinmetz (1915–2001), Austrian football (soccer) player
- Matthias Steinmetz (born 1966), German astronomer, director of the Astrophysical Institute Potsdam (AIP)
- Miklós Steinmetz (1913–1944), Hungarian-born Soviet Red Army captain.
- Paul Steinmetz (born 1977), New Zealand rugby union player
- Pierre Steinmetz (born 1943), member of the Constitutional Council of France since 2004
- Richard Steinmetz (born 1959), American actor
- Theodore Steinmetz (1880-1951), composer and World War I veteran
- William Steinmetz (1847–1903), American Union Army soldier
- Characters in Herbie movies
- Tennessee Steinmetz (Buddy Hackett), in The Love Bug
- Grandma Steinmetz (Helen Hayes) in Herbie Rides Again
- Other uses
- Steinmetz Opel Tuning, German company named after Klaus A. Steinmetz
- Steinmetz Pink Diamond, largest known Vivid Pink diamond
- 1681 Steinmetz (1948 WE), a Main-belt Asteroid named after German astronomer Julius Steinmetz (1893–1965)
- Tami Steinmetz Center for Peace Research, an academic research institution of Tel Aviv University