La Mission archeologique de l'Universite de Liege en Syrie a effectue entre 1991 et 1998 huit campagnes de fouille a Tell Amarna en Syrie. Le present rapport contient l'etude d'une eglise byzantine et de ses mosaiques mises au jour en 1998, a environ 700 m au sud du tell principal. Au moment de son degagement, cette trouvaille etait la premiere du genre dans la region. L'etude et la publication de cet ensemble, en meme temps que la restauration partielle des mosaiques, ont donne lieu a une collaboration internationale. La publication contient aussi des articles qui placent cette eglise et ses mosaiques dans son contexte geographique et historique. The Archaeological Expedition of the University of Liege to Syria conducted eight seasons of excavations at Tell Amarna, Syria, between 1991 and 1998. The present excavation report contains a study of a Byzantine church and its mosaics discovered in 1998, approximately 700 m south of the main tell. At the time, this finding was the first of its kind in the region. The study and publication of this discovery, along with the partial restoration of the mosaics, gave rise to an international collaborative project. The present report also contains articles which place this church and its mosaics in their geographical and historical context.