Mordvin Neopaganism, or the Mordvin native religion or Erzyan native religion, is the modern revival of the ethnic religion of the Mordvins (Erzya and Moksha), peoples of Volga Finnic ethnic stock dwelling in the republic of Mordovia within Russia, or in bordering lands of Russia. The religion is often called Mastorava (Mordvin for: "Mother Earth"), from the homonymous epic poem or the mother goddess of the Mordvin pantheon. The name of the originating god according to the Mordvin tradition is Ineshkipaz.
The Mordvins have been almost fully Christianised since the times of Kievan Rus', although Pagan customs were preserved in the folklore and a few villages completely preserved the native faith at least until further missionary activities of the Russian Orthodox Church in the 17th century and in the early 20th century. The Neopagan revival was started in 1990, alongside that of many other native religions in Russia, as the Soviet Union was on the brink of dissolution.
According to scholar Victor Schnirelmann, 2% of the Mordvins adhere to the Mordvin native faith, while more recent figures by the Evangelical database Joshua Project report 5%. Adherents of the Erzyan Mastor organisation organise the (Mordvin for: "Native Prayer"), a national Mordvin worship service held yearly, with participation also of members of the Mastorava organisation and other ones.