This article explores the concept of humanism in Letters to His Son by Philip Dormer Stanhope, 4th Earl of Chesterfield. The study analyzes how Chesterfield’s letters reflect the ideals of eighteenth-century Enlightenment humanism through moral education, personal development, and social behavior. The author emphasizes that a person’s true value is determined not by social status or noble origin, but by intellectual ability, virtue, politeness, honesty, and respect for others. Through practical advice addressed to his son, Chesterfield promotes such humanistic qualities as kindness, diligence, tolerance, self-discipline, charity, and compassion. The article also examines the writer’s views on education, etiquette, communication, and self-improvement as essential elements in the formation of an ideal individual. Particular attention is paid to the moral and philosophical messages contained in the letters, including the importance of keeping one’s word, respecting teachers, helping others, and behaving courteously in society. The research concludes that Chesterfield’s letters represent an important example of Enlightenment humanism and demonstrate the author’s belief that education and moral refinement are the foundations of a successful and honorable life.