This work falls within the framework of the study of acculturation processes of natives and immigrants. Its goal is to test an explanatory multi-group model of natives' acculturation attitudes as a function of diverse psychosocial variables: Prejudice and natives' appraisal of their own culture (in a direct way) and inter-group contact and perceived inter-group similarity (in an indirect way). Participants were 499 Spaniards surveyed for their attitude towards Romanian immigrants and 493 towards Ecuadorian immigrants. The indicators used took into account three socio-cultural spheres: peripheral, intermediate and central areas. This multi-group model shows an adequate fit to the data.