Objectives: This study investigated the joint long-term impact of witnessing interparental violence and experiencing child physical maltreatment on young adults' trauma symptoms and behavior problems. It also explored Chinese traditional beliefs as a possible contributor to young adults' trauma and behavior. Methods: This study used self-reporting measures to collect data from a national proportionate stratified sample of 1,924 college students in Taiwan. The sample was divided into four groups: no violence; interparental violence only; child physical maltreatment only and dual violence, to compare the combined effect of dual violence on long-term outcome with the no violence group and the one type of violence group. Results: The results indicated a significant association of interparental violence and child physical maltreatment, and 11.3% of participants reported witnessing partner violence between parents and experiencing physical maltreatment during childhood. Participants experiencing dual violence reported more trauma symptoms and behavior problems than did those experiencing only one form of violence or none at all. Exposure to both interparental violence and child physical maltreatment during childhood is a significant predictor of young adults' trauma symptoms and behavior problems, after controlling for other potentially confounding risk factors. Cultural factors also play a significant role in predicting young adults' trauma symptoms and internalizing behavior problems, after accounting for control variables and violence-related variables. Moreover, cultural factors interact significantly with dual violence experiences in predicting young adults' externalizing behavior problems. Conclusions: This study extended Western co-occurrence study findings with large Taiwanese community samples. The results demonstrated that dual violence experiences during childhood have long-term detrimental impact on young adults' trauma symptoms and behavior problems. Cultural beliefs and their interaction with dual violence experiences play a significant role in young adults' trauma symptoms and behavior problems as well. Practice implications: The present findings underscore the need for interventions for young adults exposed to childhood dual violence. Moreover, the findings highlight the need for culturally sensitive interventions to address the cultural factor impact on young adults' trauma symptoms and behavior problems. (Contains 1 figure and 7 tables.)