Background <p>Adolescents with depression often exhibit significant impairments in executive function and are prone to a vicious cycle of “depression – executive dysfunction”. Regular physical exercise has been consistently shown to benefit executive functioning, research specifically targeting depressed adolescents remains limited. Basketball, as a structured team sport conducted within school settings, offers unique advantages for improving executive function in depressed adolescents. However, studies in this area remain scarce. This study aimed to investigate the effects of an 8-week school-based basketball intervention (three 40-minute sessions per week) on executive function and depression severity in adolescents with depression, with the aim of providing effective school-based exercise interventions.</p> Methods <p>Executive function was assessed pre- and post-intervention using the Flanker task (inhibitory control) and the N-back task (working memory). The CES-D, PHQ-15, and POMS were administered to assess participants’ levels of depression, somatic symptoms, and mood states. During the 8-week intervention, participants in the experimental group engaged in structured basketball sessions, while those in the control group remained seated for self-study. A two-way repeated measures ANOVA was employed to assess the intervention effects, followed by Pearson correlation analysis to examine the association between executive function improvement and changes in depression severity.</p> Results <p>A total of 50 adolescents with depression were included in the final analysis (29 in the experimental group and 21 in the control group). Compared to the control group, participants in the experimental group exhibited significantly reduced reaction times on the Flanker task under both the congruent condition (<i>p</i> = 0.033) and the incongruent condition (<i>p</i> &lt; 0.001) after 8 weeks of intervention. Similarly, significant reductions in reaction times were observed on the N-back task for both the 0-back (<i>p</i> &lt; 0.001) and 2-back (<i>p</i> &lt; 0.001) conditions. In addition, scores on both the CES-D (<i>p</i> = 0.001) and PHQ-15 (<i>p</i> = 0.001) were significantly decreased. Further Pearson correlation analysis revealed a moderate positive correlation between the reduction in 2-back reaction time and the decrease in CES-D scores (<i>r</i> = 0.522, <i>p</i> = 0.004).</p> Conclusion <p>An 8-week school-based group basketball intervention significantly improved executive function, depression severity, and somatic symptoms in adolescents with depression, with improvements in working memory being closely associated with reductions in depression severity.</p>