Risk of developing of emotional and behavioral mental health problems increases markedly during adolescence. Despite this increasing need, most adolescents, particularly ethnic minority youth, do not seek professional help. Informed by conceptual models of health behavior, the current study examined how cultural values are related to help-seeking among adolescents from two distinct racial/ethnic groups. In a prospective survey design, 169 10th and 11th grade Vietnamese American and European American youth reported on their mental health need, as measured by emotional/behavioral mental health symptoms and stressful life events, with participants reporting on their help-seeking behavior at 6-month follow-up assessments. Multinomial logistic regression analyses indicated that mental health need interacted with cultural values and ethnicity to predict help-seeking behavior. Specifically, associations between symptoms and stressful life events, and help-seeking behavior were smaller among Vietnamese American adolescents, and among adolescents with strong family obligation values. These results underscore the complex sociocultural factors influencing adolescents’ help-seeking behavior, which have important implications for engaging youth in needed mental health care.