The library of the George & Mathilde Salem Foundation (Aleppo, Syria) is one of the most important private collections of manuscripts in the Syrian Arab Republic. It contains 547 volumes in Arabic, Syriac and other languages about Christian and Islamic theology, philosophy, history, grammar, science (mathematics, medicine, pharmacy, alchemy, agronomy and veterinary) liturgy, poetry and literature. Paul Sbath (1887-1945) devoted himself to gather oriental manuscripts "in order to serve the faith and the science." To fulfil his aim, he acquired many of them in Syria, Lebanon and Egypt, collecting more than 1325 books. Years later, he sold 775 copies to the Vatican Library: the others remained at Aleppo and - after his death - were integrated in the collection of the George & Mathilde Salem Foundation. A first description of these copies was made by Sbath in his work Bibliotheque de Manuscrits, published between 1928 and 1934, but two facts justify a new catalogue: 1) The collection has suffered significant changes, and 2) the information provided by the first owner should be enlarged and corrected. This work, addressed to researchers, offers a detailed record of these manuscripts. The copies have been classified according to linguistic criteria. The contents and the features of each work are fully described. The work includes indices of titles, personal names, subjects and places.