La transmission des sciences consiste en trois etapes: la traduction des traites anterieurs, l'assimilation des acquis theoriques, le perfectionnement des techniques et des doctrines. L'objectif de cette etude est l'analyser des grandes etapes du phenomene de transmission de la culture grecque aux Arabes, phenomene que le Peri; tw'n ejptamhvnwn brefw'n de Galien, commentaire d'un extrait du Peri; ovktamhvnou d'Hippocrate, traduit en arabe par Hunayn b. Ishaq et commente par Thabit b. Qurra semblait illustrer parfaitement. Transmission of sciences is composed of three steps: translation of treatises, assimilation of theoretical knowledge and development of technology and doctrines. The purpose of this study is to analyze steps of transmission of sciences from Greece to Arabs. This phenomenon is illustrated by a Galenic treatise, the Peri; tw'n ejptamhvnwn brefw'n which is a commentary of Hippocratic Peri; ovktamhvnou, and which is translated in Arabic by Hunayn b. Ishaq and then commented by Thabit b. Qurra.