OBJECTIVE: To explore the effect of acculturation attitudes and ethnic and national identity on behavior problems in arctic minority adolescents in northern Norway. METHOD: The Youth Self-Report, the Multigroup Ethnic Identity Measure, and acculturation strategies were completed by 581 indigenous Sami and 291 Kven high school students in 1994-1995, at age 15-18 years. Response rate was 85%. Behavior problems were in addition to ethnic/national identity and acculturation attitudes studied in relation to ethnicity, gender, age, socioeconomic status, parentage, ethnic language, and ethnic context. RESULTS: Although there were no ethnic group differences in behavior problems, the impact of ethnocultural predictors differed between ethnocultural and indigenous adolescents. Acculturation attitudes were most significant for indigenous adolescents' mental health, and identity issues showed the strongest impact on ethnocultural peers. The study revealed significant gender differences regarding the influence of ethnocultural factors, and contextual variation among Sami adolescents with the strongest impact in contexts with low density of Sami people. CONCLUSIONS: The significant ethnic group variations emphasize the importance of conducting both between- and within-group analysis on the impact of ethnocultural issues on behavior problems in minority adolescents.