Background and Aim : A significant part of healthcare-associated infections (HCAIs) is usually associated with the use of devices such as indwelling intravascular and urinary catheters, which can cause an increase in long-term hospitalization, cost, and morbidity and mortality. This study was performed to survey the microbiological characteristics of catheter-related bloodstream infection in the North of Iran.Methods : This retrospective study was carried out on inpatients with catheter-related bloodstream infection (CRBSI) over two years during ۲۰۱۸ and ۲۰۱۹. Standard microbiological and biochemical methods were followed for bacterial isolation and identification. Antimicrobial susceptibility test was performed by disk diffusion method.Results : Out of ۲۸۷ examined catheters, ۹۵ (۳۳.۱%) cases were positive with significant bacterial growth. The most prevalent causes of CRBSI were coagulase-negative staphylococci (۲۸.۴%), followed by Staphylococcus aureus (۱۵.۸%), Klebsiella pneumoniae (۱۴.۷%), and Pseudomonas aeruginosa (۱۲.۶%). Antibiotic susceptibility test showed that amikacin, co-trimoxazole, and tetracycline were the most effective antibiotics against staphylococci as the predominant cause of CRBSIs. Meanwhile, ۳۳.۳% of S. aureus isolates and ۵۶% of coagulase-negative staphylococci were methicillin-resistant. Ciprofloxacin, piperacillin-tazobactam, and gentamicin were the most effective antibiotics against K. pneumoniae isolates. Among non-fermentative Gram-negative bacilli (NFGNB), P. aeruginosa isolates showed the highest susceptibility to ofloxacin and imipenem. While gentamicin was the most effective antibiotic against Acinetobacter baumannii isolates. Conclusion : Our study showed a remarkable rate of catheter-associated infection, which demanded a more restricted and effective infection control policy. Moreover, our results provided important information for suggestions of proper antibiotics administration based on the local antibiotic susceptibility patterns.