Objectives: This study was conducted to evaluate the impact of a school-based depression awareness education program on depression knowledge and help-seeking orientation for adolescent. Methods: The students of two high schools were allocated to the intervention (n=221) or control group (n=223) by class unit. The school-based depression awareness education was a 3-session program. The intervention group received pre, post and follow-up tests while the control group received pre and follow up tests after two months. Depression knowledge, attitude to friends’ depression, and help-seeking for professional assistance was evaluated at each test. Differences in the two month change between the intervention and control groups were analyzed by t-test or chi-square test. Results: There were positive changes in depression knowledge, response to friend's depression, and attitude to professional help-seeking in the post test compared to the pretest among intervention group. Improvement of depression knowledge was greater in the intervention group than in the control group (P=0.011), but there were no significant differences in response to friend’s depression (P=0.268) or help-seeking orientation (P=0.263) after two months. Conclusions: This study revealed the school-based depression awareness education program would improve the level of knowledge on depression. Dissemination and implementation ofthe program could be suggested.