The library was established in 1963 by the creation of the first book fund of the Library of the Cathedral of Reunification in Alba Iulia. The fund included 200 copies, books donated by the Most Holy Veniamin Nistor, Bishop of Caransebeş (1886-1963), forced by the communist regime to retire in the last part of his life to the Cathedral of Reunification in Alba Iulia.

In 1975 the Orthodox Diocese of Alba Iulia was established, and the Library of the Cathedral of Reunification became the Library of the Diocese Center. Since 1991 the library has been included in the university and high school system, supporting with the book fund the two theological educational institutions: Simion Stefan Theological Seminary and the Faculty of Theology from the University of Alba Iulia. On January 30, 2007 the new headquarters of the library, located at the basement of the Faculty of Orthodox Theology building in Alba Iulia, was inaugurated, receiving the title of The Library of the Archdiocese and the Faculty of Theology.

The library holds a rich collection of scientific and documentary books (40,000 book volumes and 18,000 periodicals), which comes from the acquisition and donation of book collections belonging to professors of theology and personalities from cultural life or institutions: pr. prof. dr. Athanasia Negoiţă, pr. prof. dr. Dumitru Stăniloae, prof. dr. Olympus Căciula, Dr. Ioan Cureu, prof. archid. dr. Emilian Vasilescu, pr. prof. dr. Nicolae Neaga, prof. I. Ungur, prof. Eugen Hulea, prof. Ion Berciu, Archbishop Prof. Dr. Andrei Andreicut, pr. conf. dr. Remus Onisor, pr. prof. Nicolae Dănila, Library of the Holy Synod, National Reserve of Publications,

The library's publication funds cover various fields such as: theology, literature, history, archaeology, art, philosophy, pedagogy, psychology, ethnography, sociology, media, economics, management, law and public administration, political science, medicine, computer science.