Fear, as one of the most fundamental psychological and moral disturbances of the human condition, occupies a central place in the Hellenistic philosophies, traditions that conceived philosophy as a form of rational therapy for the soul. The principal question of this study is how the Epicureans and the Stoics explain the nature of fear and on what theoretical grounds they articulate two distinct models—ataraxia and apatheia—as strategies for overcoming it. The aim of the research is to offer a comparative analysis of these two concepts and to assess their respective capacities for providing a philosophical account of mental health. The method employed is analytical and interpretive, based on a close reading of classical Epicurean and Stoic texts, together with a conceptual comparison of the epistemological and ethical presuppositions underlying each school. The central hypothesis of the article is that, despite their metaphysical and teleological differences, both traditions construe fear as a cognitive phenomenon dependent upon erroneous judgments and locate its therapy in the correction of rational attitudes.The originality of the study lies in its reinterpretation of ataraxia and apatheia not merely as desirable psychological states, but as two systematic models of philosophical therapy, each offering a distinct logic for confronting fear: the former through the elimination of groundless and non-natural fears, and the latter through a redefinition of values grounded in the distinction between what is within our control and what is not. The article ultimately argues that these two models, taken as complementary rather than mutually exclusive,