Objective: Although the majority of non-suicidal self-injurious behaviors begin at adolescence, there are limited researches that studied adolescents with this behavior in our country. The aim of this study was to evaluate the psychiatric symptoms, identity formation and self-esteem characteristics of adolescents with non-suicidal self-injurious behavior. Methods: Forty-eight adolescents aged between 12 and 17 with non-suicidal self-injurious behavior who admitted to the adolescent psychiatry outpatient clinic and 49 adolescents with the same age who admitted to the same clinic with psychiatric symptoms other than non-suicidal self-injurious behaviour were included. Brief Symptom Inventory, Sense of Identity Assessment Form and Rosenberg Self-esteem Inventory were used to evaluate the psychiatric symptoms, the identity formation and the self-esteem of adolescents, respectively. Results: The adolescents with non-suicidal self-injurious behaviour experienced more psychiatric symptoms and identity confusion compared to the control group. The lower self-esteem observed in adolescents with nonsuicidal self-injurious behavior was found to be related to associate psychiatric disorders rather than the nonsuicidal self-injurious behavior itself. Conclusion: Adolescents with non-suicidal self-injurious behavior constitute a high-risk group with regard to psychiatric symptoms and complications. Researches investigating the developmenttal risk factors of non-suicidal self-injurious behavior in adolescents will contribute to the promotion of preventive mental health policies and effective intervention programs.