Patients with pediatric cancer face an increased risk of infections. In most cases, these infections are associated with the use of a long-term central venous catheter. This study describes the epidemiology of a port-associated bacteremia as well as a profile of microorganisms responsible for port-associated bloodstream infections (PABSIs) in pediatric patients with cancer treated in a single center. The retrospective analysis included patients with cancer who had implanted a port, hospitalized between 2010 and 2015 at the Department of Pediatric Oncology, Hematology and Bone Marrow Transplantation, Poznan University of Medical Sciences. The medical records of patients were reviewed for demographic characteristics, diagnosis, port-related complications, and their management. Data were collected from patients’ electronic medical records containing complete information on medical examinations and supplementary tests, diagnosis, timing, and type of port-associated complications. In a study period, 277 ports were inserted to 241 patients. A total of 183 094 catheter days were analyzed. Sixteen patients had more than 1 insertion of a port. The commonest observed complication was PABSI (40.07%) and the incidence density was 0.6 per 1000 port-days. Staphylococcus was the most commonly isolated organisms from patients with PABSI. From all port-associated complications, bloodstream infections and mechanical complications were the most often observed complications. The commonest pathogens responsible for PABSI were coagulase-negative staphylococci. Pathogens resistant to standard antibiotic treatment play an important role in PABSI, with methicillin-resistant Staphylococcus epidermidis being the predominant pathogen. Port-associated bloodstream infections are a common reason for preterm removal of a port.