Introduction: Multi-drug-resistant bacteria surveillance (MDR) systems are used to identify the epidemiology of MDR bacteria in neonates and children. This study aimed to describe the patterns by which MDR bacteria colonize and infect neonatal (NICU) and pediatric intensive care unit (PICU) patients in the state of Rio de Janeiro State, Brazil. Methods: A cross-sectional survey was performed using electronic data on NICU and PICU patients reported to the Rio de Janeiro State MDR bacteria surveillance system. All healthcare institutions that reported at least one case during the study period were included. Results: Between 2014 and 2017, 10,210 MDR bacteria cases, including 9261 colonizations and 949 infections, were reported. Among the colonizations, 5379 occurred in NICUs and 3882 in PICUs, while 405 infections occurred in NICUs and 544 in PICUs. ESBL producing Klebsiella sp and E. coli were the most reported colonization-causing agents in NICUs (1983/5379, 36.9%) and PICUs (1494/3882; 38.5%). The main causing bacteria reported in catheter-associated bloodstream infection (CLABSI), ventilator associated pneumonia, and catheter-associated urinary tract infection in NICUs were Klebsiella sp and E.coli (56/156, 35.9%), carbapenem-resistant Gram-negative bacteria (CRGNB) (22/65, 33.9%), and CRGNB (11/36, 30.6%) respectively, while in PICUs, they were MRSA (53/169, 31.4%), CRGNB (50/87, 57.4%), Klebsiella sp and E.coli (18/52, 34.6%), respectively. Conclusions: MDR Gram-negative bacteria (ESBL producers and carbapenem-resistant bacteria) were the most reported agents among MDR bacteria reported to Rio de Janeiro surveillance system. Except for CLABSI in children, they caused all deviceassociated infections in NICUs and PICUs.