OBJECTIVE: The aim of this paper is to explore the prevalence of psychiatric morbidity in different immigrant groups in Spain. In keeping with prior studies carried out in Europe, it is expected that the immigrant population will have elevated levels of psychopathology, with some variation across immigrant groups. METHOD: Design: Multicenter, observational, cross-sectional study. Setting: Primary care settings of two Spanish regions. Sample: N=1.503 immigrants paired with the same number of Spanish controls, adjusted by gender and age. Variables: Demographic variables, MINI International Neuropsychiatric Interview and Standardized Polyvalent Psychiatric Interview, somatic symptoms section. Student's t tests, ORs and logistic regressions were used to analyze the data. RESULTS: No differences in psychiatric morbidity were found (native born 30.9%, population vs. immigrants 29.6%, OR=.942, CI=.806-1.100) when comparing immigrants to native born Spaniards. Relative to Spaniards (30.9%), Latin American immigrants had significantly higher levels of psychopathology (36.8%), Sub-Saharan Africans (24.4%) and Asians (16%) had significantly lower levels, and Eastern Europeans (31.4%) and North Africans (26.8%) showed no significant difference. CONCLUSIONS: The hypotheses were only partially supported. Although overall immigrants did not differ from the native born population, when analyzed by geographic origin, only Latin Americans had higher levels of psychopathology. It is concluded that multiple factors need to be taken into consideration when studying the mental health of immigrants given that different immigrant groups have different levels of psychopathology.