Background factors of male genital self-mutilation have been suggested in a small series of cases. A review of 110 cases in the literature revealed that guilt feelings associated with sexual conflicts were the most important factors in the act of psychotic self-mutilation and also related to religious psychotic experiences that were often the direct motives for the act. Self-mutilators with sexual guilt feelings were likely to mutilate themselves more severely than those without. Even excluding transsexuals, disturbance of sexual identity was most participating in the act of nonpsychotic self-mutilators. In addition to these, previous history of self-injury took part in the act independently.