Filotheou monastery (Greek: Μονή Φιλοθέου) is an Eastern Orthodoxmonastery at the monastic state of Mount Athos in Greece. It stands on the north-eastern side of the peninsula. It was founded by the Blessed Philotheus, in the end of the 10th century. The monastery ranks twelfth in the hierarchy of the Athonite monasteries.
The library holds 250 manuscripts, and 2500 printed books (of which 500 are in Russian and Romanian).