The present study aimed to investigate the effectiveness of the Positive Parenting Program (Triple P) on parent–child relationships and children's quality of life among mothers of children with behavioral problems. This applied research employed an experimental design with pretest–posttest and a control group. The statistical population included all mothers of children with behavioral issues who had sought services at the Education Department’s counseling center in Qom. From this population, 30 mothers were purposefully selected and randomly assigned to experimental (n = 15) and control (n = 15) groups. The experimental group participated in eight weekly 90-minute group intervention sessions held at the Counseling Center. Data were collected using the Rutter Behavioral Problems Questionnaire (1967), the Parent–Child Relationship Scale (Pianta, 1994), and the Pediatric Quality of Life Inventory (Varni et al., 1999). The results showed significant differences between the experimental and control groups in parent–child relationship dimensions (conflict, intimacy, and dependency) and children's quality of life. Specifically, the Positive Parenting Program led to increased intimacy, reduced conflict and dependency in the parent–child relationship, and improved children's quality of life. These findings carry practical and preventive implications for psychologists, counselors, education authorities, and as well as clinicians working in child and family therapy.