Zacharias Ferreri or Ferrari (1479–1524) was an Italian monk and papal legate, Latin poet and ecclesiastical writer.

As a student in Padua, he became a Benedictine monk at the Abbey of Monte Cassino.

He served Pope Julius II but soon joined ranks of his opponents and attended the Conciliabulum of Pisa in 1511.

[1] He made peace with the new Pope Leo X and was tasked with preparing a new, shorter and more convenient, edition of the breviary.

After the death of Pope Leo X on 1 December 1521, he claimed his rights as Bishop of Guardialfiera then occupied by Valentinus de Valentiuis.