This study used longitudinal data to verify the mediating effects of depression and social withdrawal on the impacts of neglectful and intrusive parenting behavior on adolescents’ interpersonal relationships with peers and teachers in school. We used data from the Korea Children and Youth Panel Survey’s (KCYPS, 2010) 4-6th waves, which followed fourth graders across Korea. To analyze the data, we conducted a descriptive analysis, bivariate correlation analysis, and structural equation modeling. Specifically, the results showed that depression and social withdrawal had a greater indirect effect on the link between neglectful parenting behavior and relationships with peers and/or teachers than did intrusive parenting behavior. Based on these findings, we also highlighted the importance of parenting behavior in improving relationships with peers and teachers as well as the need for tailored interventions based on adolescents’ degree of depression and social withdrawal.