Background and aims: Nonsuicidal self-injury (NSSI) is highly prevalent in adolescents and is associated with various mental health problems. Repetitive NSSI (R-NSSI), as an extreme manifestation of NSSI, is a growing concern and has been proposed as a behavioral addiction. However, little is known about the potential addictive mechanisms of NSSI. This study aimed to examine the mediating effect of emotion dysregulation and the moderating effect of impulsivity using the Interaction of Person-Affect-CognitionExecution (I-PACE) model in adolescents who repeatedly engage in NSSI. Methods: A total of 3,915 adolescents (mean age 5 13.21 years, SD 5 0.87, 57.6% male) were recruited from three middle schools. Relevant questionnaires were used to evaluate childhood maltreatment, emotion dysregulation, impulsivity, and NSSI. Mediation and moderated mediation analyses were conducted separately for adolescents with occasional NSSI (O-NSSI) and R-NSSI to assess the relationship between childhood maltreatment, emotion dysregulation, impulsivity, and NSSI frequency. Results: Our study found that childhood maltreatment was directly related to NSSI and indirectly related to NSSI through emotion dysregulation in both the R-NSSI and O-NSSI groups. Furthermore, impulsivity played a moderating role in the relationship between emotion dysregulation and NSSI in the R-NSSI group but not in the O-NSSI group. Discussion and conclusions: The findings suggest that a high level of impulsivity and a high level of emotion dysregulation may be important risk addictive factors of NSSI through childhood maltreatment. Strengthening the emotion regulation skills and inhibitory control of adolescents with NSSI would be helpful to reduce their self-injury behaviors and maintain their mental health. This finding also supports the validity of the I-PACE model for evaluating R-NSSI.  Kulcsszavak: childhood maltreatment, emotion dysregulation, addictive behaviors, impulsivity, repetitive nonsuicidal self-injury