Burtas or Bortas (plural Bortaslar) were a tribe of uncertain ethnolinguistic affiliation inhabiting the steppe region north of the Caspian in medieval times. (modren Ulyanovsk Oblast and Saratov Oblast of Russian Federation). They were subject to the Khazars.

The Burtas were long believed to be a Finno-Ugrian tribal confederacy, the ancestors of the modern Moksha Mordvins group of the Mordva people as well as some groups of Volga Tatars and Chuvash. This is still the majority view.

Recently, some scholars have challenged the conventional theory, suggesting that the Burtas were actually Alans or another Iranian ethnolinguistic group.