Introduction. Healthcare-associated infections (IAAS) increase neonatal morbidity and mortality. Identifying the microbiological profile and sensitivity of the microbiota allows us to reduce infection rates, rationalize the use of antibiotics and improve neonatal survival. Objectives. To know the environmental microbiota and antimicrobial sensitivity in the Department of Neonatology (DN). Methods. Observational, descriptive, cross-sectional study, carried out between April and May 2021, in the Intensive Care, Intermediate and Immediate Care services of the DN of the Instituto Nacional Materno Perinatal, a reference center for maternal and neonatal care. 144 surfaces were selected from the hospitalized patient environment. Using swabbing technique, samples were obtained and then seeded in common and selective culture media. Sensitivity was determined using Kirby-Bauer diffusion disks, the...