Objective: We applied self-determination theory to examine a model whereby perceived parental autonomy support directly and indirectly affects nonsuicidal self-injury (NSSI) through difficulties in emotion regulation. Method: 639 participants (53% female) with a mean age of 13.38 years (SD = 0.51) completed the How I Deal with Stress Questionnaire as a screener for NSSI, the Perceptions of Parents Scale, and the Difficulties in emotion Regulation Scale. Participants who indicated having ever hurt themselves on purpose without the intent to die (n = 116, 66% female) were classified in the NSSI lifetime group. Results: A mediation analysis with bootstrapping procedure revealed that adolescents who reported their parents as being less supportive of their need for autonomy were more likely to have engaged in NSSI. Further, this relationship was partially mediated by emotion regulation. Conclusion: Adolescents who do not perceive autonomy support from their parents, have more difficulties regulating their emotions, and may turn to NSSI as a means to cope. Clinical implications of the findings suggest involving the family, and specifically, targeting parental autonomy support may be beneficial when working with young adolescents who self-injure.