Teen dating violence (TDV) and school violence (SV) are two major social problems in adolescence. Until recently, the antecedents of both TDV and SV have been analyzed largely independently of each other. This study analyses and compares the determinants of both TDV and SV, with a focus on physical violence. Based on a comprehensive survey of ninth-grade adolescents at the average age of 15 years (N = 3,800) conducted in the German federal state of Lower Saxony, the findings showed that there is a significant but low correlation between both physical TDV and SV (r = 0.21). Concerning the determinants, we found that males carry out physical SV significantly more often, but physical TDV significantly less often than female respondents. Acquaintance with violent friends shows a stronger correlation with SV but not with TDV. Low self-control and violent media consumption are determinants of both TDV and SV. Empathy as a protective factor and parental violence as another risk factor were found to be only weak and sometimes not significantly correlated with both TDV and SV.