Mar Matti or Mattai (St. Matthew) is the name of a Syriac Orthodox (Jacobite) monastery that sits atop Mount Maqlub (also known as Alphaph or Alfaf Mountain) at the height of 2,010 feet above sea level. It is located 15 miles from Nineveh and just under 13 miles northwest of Mosul.

The monastery now serves the small farming villages located at the foot of the mountain.

Mar Matti Monastery is only the mere shadow of its former magnificence. The small monastic community which still lives there watches over an immemorial heritage. It is recognized as one of the oldest monasteries, dating back to 363 AD. King Sennacherib built it during the reign of the Prussian King Shaboor (Shapur).

Seated on the shelf of a rocky peak, the monastery offers an exceptional double view. As seen from the valley, it appears as being suspended between the earth and the sky and leads us to meditation. On the other side, from its terrace, it offers a 180° panorama and seems to be keeping a watchful eye on the world below, the world of the people of Nineveh.

Mar Matti was buried among many bishops, monks, and priests in this monastery. It was well known for its large library and Syriac Christian manuscripts. Also buried in Mar Matti Monastery is one of the great scholars at that time, Ibn Al Ibry. Many caves and silos remain around the monastery; they used to house all the people that lived there.