The textbook “History of Ancient Philosophy” by Archpriest Vladimir Mustafin, Candidate of Theology, Professor of the Department of Theology of the St. Petersburg Theological Academy, examines the history of ancient philosophy from Thales (640-545 BC) to Proclus (412-485) in all its periods - emergence, development and systematization. The main conclusion from the entire history of ancient philosophy is the recognition of the inconsistency of its main epistemological plan - to see in the individual human mind an independent and self-sufficient source of true metaphysical knowledge, accepting as such a source the one that has always been recognized in traditional religious teachings - divine Revelation. Recommended for teachers and students of theological educational institutions, theological faculties of secular universities, as well as all students of the history of philosophy. The publishing layout is saved in PDF A4 format.