Parent-child relationships play an important role in successful academic outcomes. Previous research suggests that the association between parent-child relationships and offspring's academic achievement may be mediated by offspring's self-efficacy levels, although these relationships are not fully understood. Furthermore, the association between family support and academic outcomes is well-documented among European Americans, but not across cultures. Therefore, the present study examined how parent-child relationship quality relates to young adults' academic achievement and self-efficacy among European Americans and Asian Americans. Participants were 258 undergraduate students (85 male, 173 female) who completed a survey. Overall, both parent-child relationships and self-efficacy were significantly associated with the offspring's academic performance, and self-efficacy mediated the relationship between parent-child relationships and school outcomes. Ethnicity moderated these relationships: among European American students, quality of parent-child relationships was not associated with self-efficacy level whereas for Asian Americans, parent-child relationships were associated with self-efficacy. These findings suggest that European American college students' self-efficacy levels are less dependent on parent-child relationship quality, but for Asian Americans college students it may be important for educators to facilitate communication and family support so students may continue to use family as a resource for self-efficacy levels.