Nikita Pustosvyat was an Eastern Orthodox priest who became a prominent leader of the Russian Old Believers. Born Nikita Konstantinovich Dobrynin, he served in Suzdal and assisted in the revision of liturgical books under Patriarch Joseph. He is best known for his staunch opposition to the church reforms of Patriarch Nikon, which led to the Great Schism. Following his legal disputes with the ecclesiastical authorities, he became a central figure in the movement of those upholding the old traditions during the late 17th century.