Background and aims: Problematic smartphone use (PSU) has become an important public health issue in adolescence, and it is imperative to innovate treatments to improve and prolong the effectiveness of interventions. Considering that positive psychology interventions (PPIs) are highly effective in reducing addictive behaviors in adolescents, this study aims to develop and evaluate the effectiveness of an intervention program (PREIP, 8 weeks, 1 h/week) on adolescent PSU within a positive psychology framework. Methods: Adolescents from China were randomly assigned to the personal resources energized intervention program (PREIP) intervention group (N 5 30), the CBT control group (N 5 30), and the waitlist (N 5 28), which were measured at baseline, post-intervention, and 2-month follow-up. Results: Participants in the PREIP intervention group had significantly lower levels of PSU, and loneliness, and significantly higher levels of perceived social support and well-being compared to the two control groups (CBT control and waitlist). Furthermore, although participants in the CBT control group were able to significantly reduce PSU symptoms, the improvements in the PREIP group were more sustained over the follow-up period. Discussion and conclusions: In conclusion, this study supports the positive effects of PREIP on adolescent PSU and explained the underlying mechanisms for improving positive mood, reducing loneliness, and promoting perceived social support.  Kulcsszavak: problematic smartphone use, adolescent, loneliness, perceived social support, positive psychology interventions