<p>This study examines the relationship between physical activity levels and mental health in adolescents following an earthquake, focusing on community-based rehabilitation and interventions. A total of 389 adolescents (ages 11–17) participated in the current study. Post-traumatic stress (PTS) was assessed using DSM-5 Post-traumatic Stress Symptom Severity Scale, while depression and anxiety were evaluated using DSM-5 Level 2 Depression and Anxiety scales. Physical activity levels were measured with the Physical Activity Scale for Adolescents. Among participants, 48.3% were female and 51.7% were male. Strong positive correlations were found between Post-traumatic stress disorder (PTSD) severity and both depression (<i>r</i> = 0.738) and anxiety (<i>r</i> = 0.723), as well as between depression and anxiety (<i>r</i> = 0.754) (<i>p</i> = 0.001 for all). No significant relationship was observed between PTSD severity and physical activity or age (<i>p</i> &gt; 0.05). A weak negative relationship existed between depression and physical activity (<i>r</i>=-0.228, <i>p</i> = 0.012), while a positive correlation was found between depression and age (<i>r</i> = 0.282, <i>p</i> = 0.001). Adolescents face significant psychological effects after earthquakes. Physical activity levels may decline due to reduced motivation and opportunities. Post-traumatic stress can also cause depression and anxiety in adolescents after a disaster such as an earthquake. Therefore, it’s essential to encourage physical activity and implement appropriate programs in disaster-affected regions.</p>