Debre Bizen (ተምሳል እስራኤል ቁዱስ ቦታ ኣምላኽ ዘ ኣብርሃም, ያዕቆብ, ወ ኢሳቅ) is the best-known monastery of the Eritrean Orthodox Tewahedo Church. Located at the top of Debre Bizen the mountain (2460 meters) near the town of Nefasit in Eritrea. Its library contains many important Ge'ez manuscripts.
Debre Bizen was founded in the 1350s by Filipos, who was a student of Absadi. By 1400, the Monastery followed the rule of the House of Ewostatewos (Ancient Greek: Εὐστάθιος Eustáthios), and a gadl (hagiography) of Ewostatewos was later composed there. According to Tom Killion, it remained independent of the Ethiopian Church, while Richard Pankhurst states that it continued to be dependent on the Ethiopian Orthodox Tewahedo Church centered in Axum. In either case, a charter survives of the Emperor Zara Yaqob in which he granted lands to Debre Bizen.
- Pankhurst, Richard (1997). The Ethiopian Borderlands: Essays in Regional History from Ancient Times to the End of the 18th Century. Red Sea Press Press. p. 38. ISBN 0-932415-19-9.
- Killion, Tom (1998). Historical Dictionary of Eritrea. The Scarecrow Press. ISBN 0-8108-3437-5.
- Pankhurst, The Ethiopian Borderlands, p. 37
- George Wynn Brereton Huntingford, The historical geography of Ethiopia from the first century AD to 1704, (Oxford University Press: 1989), p. 103
- Pankhurst, The Ethiopian Borderlands, p. 234
- Richard R.K. Pankhurst, The Ethiopian Royal Chronicles (Oxford: Addis Ababa, 1967), pp. 125-9.