This longitudinal cross-lagged research attempted to examine the directions of relations between interparental conflict and aggressive behavior, with attention to the potential mediating effects of social anxiety. This study included 340 Chinese senior primary school students (51.5% boys, Mage = 10.86years, SD = 0.73). Cross-lagged panel analyses revealed that children’s interparental conflict can predict aggressive behavior over time, as well as aggression did not predict children’s interparental conflict. Besides, we found social anxiety at time1 and time 2 played a mediating role between interparental conflict at time 1 and aggressive behavior at time 2. This study might help understand the relationship between parental conflict and aggressive behavior, providing important practical basis for reducing social anxiety and aggressive behavior. Our findings contribute to understanding the relationship between parental conflict and aggressive behavior, providing important practical basis for reducing the occurrence of social anxiety and aggressive behavior.