This study presents, in the first part, the relations of the Patriarchate of Antioch with the Romanian countries from the beginning to the middle of the eighteenth century, aving as personalities involved, the Antiochian patriarchs: Joachim V Daw, Macarios III Zaim, Athanasius III Dabbas and Sylvester of Antioch the Cypriot, and on the Romanian side, their contemporary princes from Moldavia and Wallachia. Together with the presentation of these relations, it is highlighted the historic importance for the Romanians of the journey of Macarios III Zaim, the missionary and cultural activity of the Patriarchs Athanasius III Dabbas and Sylvester, following the valuing of the contributions of some Romanian and foreign authors, as well as some original or insufficiently used sources by the researchers. By deepening the relations of the last patriarch mentioned, it is presented his struggle to defend the Orthodox faith, aggressed by the propaganda of Catholic missionaries, and the justified support given by the Romanian Principalities for the printing of the first Orthodox books in the Levantine territories and for the establishment of the first Orthodox book workshop in Lebanon and especially for the salvation of this apostolic patriarchate, aggressed by political and religious opponents, by providing lasting financial resources and the dedication of two monasteries: „Saint Spyridon” from Bucharest and „Saint Nicholas” Popăuți.