Matthias Steinmetz (born 8 March 1966 in Saarbrücken) is a German astronomer and astrophysicist.
Steinmetz is a specialist in the areas of cosmology, the formation and evolution of galaxies and computational astrophysics.
For his thesis "On the formation and evolution of galaxies" he was awarded the Otto Hahn Medal of the Max Planck Society.
He was a postdoctoral fellow at the Max Planck Institute for Astrophysics and at the Department for Astronomy at the University of California, Berkeley.
In 1996 he joined the faculty of Steward Observatory at the University of Arizona in Tucson.