There is a good exemplar of ‘Islamic science’ in the first centuries of the Islamic civilization. This science had at least two different features. First, it had a logical framework to testify that it is Islamic. Second, its being Islamic was, to some extent, spontaneous. Thinkers of Islamic golden ages, between 3^rd to 8^th centuries, were not fully aware of other civilizational forms, so, their own sciences were essentially Islamic. Farabi, among philosophers (al-Falasifa), and Ibn Khaldun, among al-‘Asha’ira, both engendered sciences which were religious in all aspects of anthropology, ontology, and epistemology. In this article, we focused on an important point in the thought of Farabi and Ibn Khaldun. That is, what is the difference between Farabi’s and Ibn Khaldun’s philosophical anthropology? And whether it is possible to have a synthetic Islamic science based on the anthropology of the two thinkers? To answer this question, we chose historical-comparative approach, to find the differences between the two approaches to a so-called Islamic science.