PURPOSE: This study was done to examine levels of temperament, parent-child attachment and depression of adolescents and verify its effects. METHODS: Surveys were conducted with 500 students from two middle schools, one located in Seoul and one in Gyeonggi Province. Adolescent temperament was measured using the Junior Temperament and Character Inventory, parent-child attachment using the Revised Inventory of Parent and Peer Attachment and depression using the Children's Depression Inventory. Cluster, t-test, correlation and logistic regression were used for data analysis. RESULTS: Characteristics of temperament were classified into 2 groups. The 'Adaptation vulnerable group' showed high Harm Avoidance and the 'Adaptation protective group' showed high Reward Dependence, and Patience. The 'Adaptation vulnerable group' showed lower attachment and higher depression than the 'Adaptation protective group'. Novelty Seeking and Harm Avoidance correlated positively with depression and negatively with attachment. Students with higher levels of attachment reported lower levels of depression. The logistic regression analysis showed that the 'Adaptation vulnerable group' was 2.16 times more likely to be affected by depression than 'Adaptation protective group'. CONCLUSION: Results of this study can be used to develop depression intervention programs for adolescent psychological health and provide encouragement in the development of parent-child attachment.