The present study investigated the prevalence and environmental correlates of self-mutilation in a community sample of adolescents. It was hypothesized that self-mutilation of family members, parental conflict, poor parent-child relationships, poor peer relationships, and the poor relationship with teachers were related to adolescent self-mutilating behaviors. Gender difference was also examined. The research population was students enrolled in grades 7 to 12 in Taiwan. The multi-stage cluster sampling method was used to select study participants. The effective sample size was 1,975, 42% of whom were male, 58% were female. Data were collected by means of questionnaires administered in the group setting. Logistic regressions were used to test the multivariate model. In this sample, 22.4% of the respondents had self-mutilating behaviors. Among these people, 75.6% had harmed themselves deliberately at least twice, and 17% reported that they did it many times. The most commonly reported self-mutilating behavior was carving on skin (48.6%), followed by burning skin (26.5%). Multivariate logistic analyses indicated that in the controlled setting, the chance of self-mutilation is higher for adolescents who experienced more parental conflict, had poorer parent-child relationships, had poorer relationships with teachers, and had someone at home engaged in self-mutilation. Gender difference was also found; more girls had self-mutilation behavior than boys. Discussion and implication for future interventions are suggested.