The increase of the number of cases of AIDS among women reveals a progressive increase of the vertical transmission of HIV in Brazil, as well as in Piauí Considering the relevance of the subject, this study had as objective to analyze the conditions of the implementation of the rules and measures recommended by the Ministry of Health to prevent the vertical transmission of HIV in maternity houses of Teresina-PI. The theoretical-methodological approach included the study of organizational dynamics and its actors, by means of qualitative approach. In order to obtain data, 17 semi-structured interviews were carried out. The results revealed that the recommendations of the Ministry of Health were totally followed, making more evident the weakness of the assistance provided, to the mother/son binomial.