Bipolar disorder mostly develops before adulthood, that is, adolescents are prone to the onset of the disease characteristics, bipolar disorder is related to the following factors: 1, affected by biological factors, closely related to genetics, bipolar personality disorder are organic changes in the basis of the disease population is larger may have organic changes, the adolescent body is in the developmental period, the development process can appear organic disease; 2, bipolar disorder and Personality or psychosocial factors are closely related, such as the child introvert or have problems after the difficulty of self-resolution, it will be long-term depression, depressive tendencies, but also self-aggression and self-depreciation; 3, adolescents are not well formed in all aspects of personality, immature personality, character instability, induced by psychosocial factors, vulnerable to external factors, mood swings, and emotional stability is closely related.