We examined the relationships between three dimensions of familism: importance of family, family support, and family conflict with acculturation, assessed orthogonally (Mexican and American cultural contributions assessed independently), and the relative contribution these factors make to psychological adjustment among 248 (124 women, 124 men) adults of Mexican origin. After controlling for sociodemographic characteristics, positive associations were found between importance of family and the biculturalism of Mexican and American cultural identity; family support and Mexican cultural identity; but no associations between family conflict and level of acculturation. Psychological well-being was positively associated with Mexican cultural identity and family support, whereas psychological distress was associated with greater family conflict and lower family support. The greater relative contribution of Mexican cultural identity to familism and well-being, and the importance of assessing acculturation orthogonally are discussed.