OBJECTIVE: To compare common carotid intima-media thickness (IMT) between the two major Brazilian ethnic groups (those of African descent and those of European descent) among individuals with one or more risk factors for atherosclerotic disease. METHOD: Two hundred and six patients with one or more risk factors for atherosclerotic disease were evaluated in a cross-sectional study in which their clinical, ethnic and Demographic characteristics were collected. All patients underwent duplex ultrasound examination of their carotid vessels to obtain IMT measurements. RESULTS: One hundred and fifty-three patients (74.3%) had a carotid IMT greater than 1.0 mm at one or more point of measurement in at least one common carotid artery. There was a significant correlation between older age and mean carotid wall thickness (R=0.479 / P<0.01). Multivariate analysis identified male sex, arterial hypertension and older age as variables associated with increased IMT (P<0.05 for all variables). When IMT was compared between the two ethnic groups in this study, no significant differences were noted. Euro-descendants and Afro-descendants had similar IMT values, even when the groups were stratified by degree of IMT (normal vs. increased) and presence of stroke and/or transient ischemic attack (yes vs. no). CONCLUSIONS: The risk factors associated with increased common carotid artery IMT in Brazilian individuals are similar to those in previously described populations. No differences were observed between the two main Brazilian ethnic groups. Longitudinal studies are required for a better evaluation of the incidence, etiologic factors and evolution of carotid intimomedial thickening in this population.