Parent–child conflict is a known risk and maintenance factor for non-suicidal self-injury (NSSI) in adolescents. Seeking common ground while reserving differences (SCGWRD), a cognitive philosophy centered on managing interpersonal conflict and fostering harmonious relationships, may hold the potential for improving parent–child dynamics. However, Western-originated psychotherapeutic techniques have shown limited effectiveness in addressing NSSI in Chinese adolescents. In addition, no prior studies have adapted and innovatively applied the SCGWRD concept as a psychotherapeutic intervention targeting parent-child conflict in this population. This study aimed to describe and explore the therapeutic experiences of adolescents with NSSI and concurrent parent–child conflict, who underwent an intervention based on the SCGWRD concept. Using a qualitative research approach grounded in inductive and descriptive analysis, semi-structured in-depth interviews were conducted with 12 adolescents experiencing parent–child conflict and receiving SCGWRD-based intervention. Data were analyzed using a thematic analysis framework. Five core themes with progressive relationships were identified: (i) distinctiveness from traditional intervention models; (ii) low cognitive load during acceptance; (iii) cognitive restructuring; (iv) stabilization of negative emotions and reduction of self-injury behaviors; and (v) improvement and harmony in parent–child relationships. Moreover, most participants viewed the intervention as a turning point for self-growth, with cognitive shifts exhibiting a three-stage trajectory: Conflict deconstruction – concept internalization – behavioral adaptation. Rooted in Eastern traditional culture, the SCGWRD concept may serve as a culturally adaptive cognitive-behavioral therapeutic technique. This approach holds promise for repairing parent–child relationships in adolescents with NSSI and may contribute to the reduction of self-harm behaviors.