Purpose: The purpose of this study was to evaluate the effects of a school-based intervention program for middle school adolescent girls with depression. Methods: The study was a pretest-posttest repeated-measure design with a nonequivalent control group. Fifty eight students with depressive symptoms were recruited from two middle schools in Seoul, Korea. The data were collected from the intervention (n=30) and the comparison group (n=28). The research instrument was Reynolds Adolescent Depression Scale. Results: The intervention group greatly improved from baseline to 10 weeks and then saw a slight positive change between 10 and 13 weeks. Conclusion: The results of this research show that depression intervention programs are effective for young female adolescents. Thus the investigation has important school-based treatment implications, and should be integrated into school curriculums by school health nurses for early intervention of depressive symptoms in middle school adolescent girls.