Jan Hus is especially well-known as a preacher and theologian whose activities anticipated the European protestant reformation and the hussite movement. It should not be forgotten, however, that Hus worked for many years as a teacher at the Faculty of Liberal Arts. He was therefore also a philosopher reflecting on contemporary subjects, among which was the reception of the philosophical thought of John Wyclif at Prague University, and the discussion of the reality of universals connected with it. The study maps Hus’s realist conception of universals on the basis of an analysis of the dispersed fragments of his pronouncements on universals from his quaestiones and from his Sentences commentary. The author divides this mapping into four different contexts: (1) God’s nature and the Trinity of Persons; (2) the ideas in God’s mind; (3) being as an analogical quasi-universal; and (4) the very conception of universals, that is of genera and species. In these different thematical areas, the study shows that Hus’s realism played an important role in his philosophico-theological thought of constituting its philosophical grounding. It could be said that although Hus’s realistic attitudes were influenced to a great extent by the thought of John Wyclif, Hus rejected or softened Wyclif’s heterodox opinions and the demands stemming from realism. Hus’s metaphysical standpoint, in the writings in question, also do not show a direct connection with his thoughts on church reform.