Objective To investigate the causes of a cluster of suspected neonatal carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infection (BSI) in the neonatal department of a hospital, and provide references for the effective control of the occurrence of healthcare-associated infection (HAI). Methods Epidemiological investigation on 3 neonates with CRKP BSI in the neonatal department from January 31 to February 6, 2023 was performed. Specimens from environmental object surfaces were taken for environmental hygiene monitoring, and effective control measures were taken according to the risk factors. Results From January 31 to February 6, 2023, a total of 60 neonates were admitted in the neonatal department, including 16 with peripherally inserted central venous catheter (PICC). Three neonates had CRKP BSI, with a incidence of 5.00%. There were 33 hospitalized neonates on the day (February 7) when the cluster of HAI was reported, with a prevalence rate of 9.09% (3/33). CRKP BSI rate in the neonatal department of this hospital from January 31 to February 6, 2023 was higher than that in 2022 (P<0.001). The incubators of the 3 neonates with CRKP BSI were in the same ward and adjacent to each other. The first neonate with CRKP BSI (who developed BSI on January 31) underwent PICC maintenance on February 4, and the other 2 neonates with PICC maintenance immediately following the first one also developed CRKP BSI. CRKP were isolated from blood culture of all 3 neonates, and antimicrobial susceptibility testing results were consistent. Conclusion The occurrence of the cluster event of neonatal CRKP BSI may be related to the failure of strict implementation of aseptic procedures during PICC maintenance and cross contamination among items.