Sarmatia or Sarmatian may refer to:

• Sarmatia, the land of the Sarmatians in eastern Europe, ancient Iranian peoples closely related to the Scythians
  • Sarmatia Asiatica and Sarmatia Europea, geographical differentiation of the above
  • Sarmatian language, an Eastern Iranian language
• Sarmatia (moth), a genus of moths in the family Erebidae
• Sarmatian (age), an age in the geologic timescale of Central Europe and Central Asia
• Polish–Lithuanian Commonwealth
• Sarmatism, the lifestyle of the aristocracy of the Polish–Lithuanian Commonwealth
• Sarmatian Review, a peer reviewed academic journal
• Sarmatian Craton, in geology the southern segment/region of the East European Craton

• Sarmat (disambiguation)