This study examined the relationship between experiential avoidance, functionally equivalent behaviors, and repetitive nonsuicidal self-injury (NSSI/RNSSI) among adolescents. Self-report questionnaires from adolescents (N = 211) from 3 school-based samples were employed to assess three forms of experiential avoidance (thought suppression, alexithymia, and avoidance/cognitive fusion), various aspects of self-mutilating behaviors, and the existence of functionally equivalent behaviors (disordered eating, substance abuse, suicidal ideation/behaviors). Results indicated one third of participants reported a history of NSSI and 16% reported engaging in RNSSI in the past 6 months. Female adolescents were twice as likely as males to report a history of RNSSI. Unwanted inner experiences, thought suppression, and alexithymia differentiated adolescents with a history of NSSI from their counterparts. Functionally equivalent behaviors occurred more frequently among those with a history of NSSI and increased in severity as NSSI increased, particularly suicidal ideation and behaviors. However, results for patterns of avoidance were not as consistent for males as females, which questions the broad application of this model. NSSI continues to be surprisingly common among adolescents in the community. NSSI, particularly repetitive forms, appears to be strongly related to common forms of experiential avoidance, moreso for female adolescents. Results also illustrate the importance of conceptualizing and treating self-injury as a form of experiential avoidance.