Objective: To examine racial/ethnic patterns of parental beliefs about etiological explanations for youth problems. Method: The parents of 1,338 youths with identified mental health problems were asked about their beliefs about the causes for their children's problems from a questionnaire with 11 etiological categories. Results: Parents of African American, Asian/Pacific Islander American, and Latino youths were generally less likely than parents of non-Hispanic whites to endorse etiologies consistent with biopsychosocial beliefs about mental illness. Some racial/ethnic differences were evident for sociological causes, but none existed for spiritual or nature disharmony etiologies. Analyses controlling for factors including child symptomatology produced fewer significant racial/ethnic differences but a similar pattern of results. Conclusions: Racial/ethnic differences in parental beliefs about the causes of child problems exist in an at-risk sample, and implications for the help-seeking, utilization, and effectiveness of biopsychosocially oriented mental health services for diverse populations are discussed. J. Am. Acad. Child Adolesc. Psychiatry, 2004;43(5):605-612. Key Words: race/ethnicity, parental beliefs, cultural competence.