Matthias Greitter, also Matthäus Greiter, (ca. 1495 – 20 December 1550) was a German priest, cantor and composer.
Greitter was born in Aichach. He became priest and cantor at Strasbourg Cathedral. In 1524 he joined the new Reformed Church. In 1538 he accepted a position of music teacher at the Collegium Argentinense (later University of Strasbourg). In 1549 he moved back to the Catholic religion and founded a Catholic school of singing, but he died the following year in Strasbourg, presumably from the plague.