Background: Catheter-associated bloodstream infections (CABSIs) represent a major challenge in neonatal intensive care units (NICUs), particularly among preterm infants requiring invasive procedures. Umbilical and peripheral venous catheters are indispensable in neonatal care but pose significant infection risks. Methods: A microbiological study was conducted between 2020 and 2023 at the Research Centre for Maternal and Child Health Care in Yerevan, Armenia. Catheters removed from 109 neonates admitted to a category 3 NICU were examined to determine microbial growth and antimicrobial resistance. Demographic, clinical, and microbiological data were analyzed using descriptive statistics and chi-squared tests. Results: The mean gestational age of neonates was 31 weeks; 60% were born preterm, with 23% extremely low birth weight (<1000 g). Catheters were in place for an average of 32 hours. Microbial growth was identified in 26 catheters (24%), including 23 with bacterial isolates (21%) and 3 with fungal isolates (3%). The predominant bacterial genera were Klebsiella spp. (n=7 (27%)), Enterobacter spp. (n = 6 (23%)), Escherichia spp. and Staphylococcus spp. (both with n=4 (15%)). The susceptibility of the 23 bacterial cultures isolated from the catheters was tested against a common set of antibiotics. The discovered bacterial species were most often resistant to Vancomycin and Gentamicin in a pooled analysis (100% and 96%, respectively). Conversely, Meropenem and Ciprofloxacin showed the least resistance rate (30% and 17%, respectively). Conclusion: This study underscores the importance of microbiological surveillance in NICUs to better understand the etiology and resistance profiles of pathogens associated with CABSIs. By refining our approach to catheter management and infection control, we can enhance the safety and outcomes for neonates requiring invasive procedures. Future research should focus on improving catheter care protocols and investigating interventions that may reduce the incidence of infections in this high-risk group.