The main purpose of the article is to reveal the philosophical foundations and elements of fallibilism in the traditions of ancient philosophy and, in particular, skeptical teachings, to show the attempts of forming and applying the main principles of fallibilism in the teachings of ancient philosophers, recording the outlook and methodological importance of fallibilism in human existence and knowledge, the justification of knowledge, in the philosophical-historical process of the search for criteria of truth. To achieve the goal, the following tasks were set: to analyze the epistemological views and approaches of ancient Greek and modern philosophical teachings and authors that contributed to the formation and further development of fallibilism, and to study the outlook and methodological significance of fallibilism and its impact on different epistemological concepts and in the context of overcoming conceptual conflicts and extremes. Many original works and articles were used during the research. The research used the methods of analysis, synthesis, induction, deduction, analogy and historical comparison. The main conclusion derived from this research is that the skeptical views of many ancient Greek philosophers and especially Sextus Empiricus, Carneades, and Philo played a vital role in shaping the philosophical foundations of fallibilism and its worldviewmethodological significance. The approaches proposed by these authors facilitated the reinterpretation of classical notions of knowledge and cognition, thereby establishing alternative fallibilistic approaches to a wide range of epistemological issues. Importantly, fallibilism has historically demonstrated its significance of the outlook and methodological function in mitigating and resolving epistemological conflicts, as well as reconciling opposing and dead-end conceptual frameworks.