Objective <p>This investigation was designed to assess the mediating effects of physical exercise and depression on the relationship between family support and Internet addiction (IA) among adolescents in Western China.</p> Methods <p>A total of 807 adolescents (404 boys and 403 girls, aged 13.80 ± 1.58 years) from Western China completed a self-report questionnaire that measured family support, physical exercise, depression, and IA. We employed SPSS and the Process macro for correlation and mediation analyses.</p> Results <p>The survey results revealed an inverse association between family support and IA, along with a positive association between family support and physical exercise. IA showed a negative correlation with physical exercise and a positive correlation with depression. Physical exercise was also found to be inversely related to depression. After controlling for age and gender, mediation analysis indicated that physical exercise and depression mediated the relationship between family support and IA in adolescents.</p> Conclusion <p>This study provides a more profound comprehension of the complex pathways linking family support to adolescent IA. These findings could inform targeted interventions that leverage family support to foster physical activity and mental well-being, thereby mitigating the risk of IA.</p>