Abstract：Mencius proposed the theory of innate goodness，with virtue at its core，and adopted selfcultivation and moral nurturing as his behavioral norms. The mental health preservation in Chinese medicine is achieved through regulating emotions and nourishing the spirit， aiming for physical and mental health， and longevity. Mencius' thoughts on self-cultivation and moral nurturing are mainly reflected in three aspects：preserving the mind and nurturing the nature，treating others as oneself，and introspection. This study explores the origins and connotations of Mencius' thoughts on self-cultivation and moral nurturing， and their impact on modern health preservation concepts， in the hope of benefiting mental health preservation and the moral cultivation of contemporary people.