Background/Aims: Arteriovenous fistulae (AVF) thrombosis is a common cause of morbidity in hemodialysis (HD) patients. Increased soluble endothelial protein C receptor (sEPCR) levels have been associated with increased risk of venous thrombosis. We aimed to investigate the possible effects of sEPCR levels on the development of AVF thrombosis in adult HD patients. Methods: 60 HD patients and 22 healthy controls were included. Patients were followed for 18 months and were divided into two groups according to AVF thrombosis development: group 1 (with thrombosis) and group 2 (without thrombosis). Also, patients classified into tertiles according to plasma sEPCR levels: lowest, intermediate, and highest. Groups were analyzed for any relationship between sEPCR levels and development of AVF thrombosis. Results: Mean plasma sEPCR levels were significantly higher in HD patients than they were in controls. Group 1 patients had significantly higher sEPCR levels compared with group 2 patients. Patients’ groups were similar regarding other possible risk factors for AVF thromboses. The rate of AVF thrombosis development was significantly higher in the highest sEPCR tertile. Conclusion: This is the first study to analyze sEPCR levels in HD patients. Our findings demonstrate a relationship between plasma sEPCR levels and development of AVF thromboses.