The Pontifical Oriental Institute ("Pontificium Institutum Orientalium" in Latin, "Pontificio Instituto Orientale" in Italian) is the premier center for the study of Eastern Christianity in Rome, Italy.
The pontifical school was established in 1917 by Pope Benedict XV. Pope Pius XI entrusted the Institute to the Society of Jesus in 1922, and with the 1928 encyclical "Rerum Orientalium", encouraged bishops to send students to the Institute to be formed as future professors in Oriental studies. In that same year, Pius XI associated the Institute with the Pontifical Gregorian University and the Pontifical Biblical Institute, thus forming the Gregorian Consortium.
In 1971, the Faculty of Oriental Canon Law was erected alongside the already existing Faculty of Oriental Ecclesiastical Studies. The Faculty of Oriental Canon Law had a crucial role in the production of Code of Canon Law for the Oriental Churches.
Since 1993, the Grand Chancellor of the Oriental Institute has been the Cardinal Prefect of the Congregation for the Oriental Churches. The current Chancellor is Cardinal Leonardo Sandri. The current Rector of the Institute is the Reverend Father James McCann, S.J.
The Institute maintains an important library of Christian oriental literature. One special holding is a rare collection of Old Slavonic manuscripts.
The Institute has been located across from the Basilica of Santa Maria Maggiore since 1926. It is separated from the Collegium Russicum by the Church of Saint Antony.
According to article 16 of the Lateran Treaty, signed in 1929 between Italy and the Holy See, the property of the Oriental Institute enjoys a certain level of extraterritoriality, with the Holy See having all rights over the infrastructure without interference from the Italian State, and free from all Italian taxation.
The Institute is a member of the Gregorian Consortium.
In spoken language, the school is sometimes simply referred to as "The Orientale".