This cross-cultural study will examine both different and similar patterns in the social and psychological effects of parental divorce and marital conflict on college students in Japan and America. This study will also investigate how extended family and perception of divorce affect these young adults’ well-being. This cross-cultural comparison between collectivistic and individualistic cultures, respectively, may assist both Japanese and American researchers and policy makers to more effectively ameliorate the negative impact of divorce and marital conflict on the well-being of young adults. Moreover, it is particularly important to conduct a cross-cultural (collectivistic vs. individualistic) study on the effects of parental divorce and marital conflict in order to disclose culturally unique factors as well as any that may be universal.