The paper analyzes the infrastructure of public schools in Brazil by examining the hypothesis that the institutions with poor material conditions have students with a lower socioeconomic level. The characterization of the institutions is based on data from the 2013 School Census, submitted to latent class modeling, which revealed the existence of four different school profiles. In order to carry out a socioeconomic differentiation of the institutions, the Poverty In School Indicator (IPE in Portuguese) was created, which uses data from Bolsa Família, an income transfer program. The results confirm the available body of literature on the subject by showing that the location, the administrative dependency, the size of the school and the region of the country in which it is inserted are related to the inequalities of school infrastructure. In addition, the study finds that the public schools with better infrastructure conditions generally have lower proportions of poor students. On the other hand, most institutions with the worst infrastructure profile have mostly poor or extremely poor students, confirming the hypothesis of this research.