This paper expounds the cognitive characteristics in the process of information processing of self-deception, analyzes the posittve effects of self-deception on indtviduals, and puts forward a dialectical perspecttve to review the positive effectof self-deception on indtviduals. We believe that short-term self-deception has positive effect on indtviduals, but long-term of self-deception which lacks real self-perception will hinder the development of indtviduals. Temperate self-deception is based on the balance of positive and negative psychological states of individuals to improve self-adaptability by acttvely regulating mental health, subjective well-being and interpersonal relatlonships, rather than completely avoid negattve information about self.