In this research it is presented a demographic analysis, it was investigated the function of the migration in the formation process and urban expantion of the Metropolitan Region of Fortaleza (MRF) and its social-spatial segregation process between the decades of 1990, 2000 and 2010. Thus, this work checks the function of migration in the configuration of the center and the periphery into the MRF, pointing for the social-spatial segregation of the population.