Background: Nurses in hemodialysis (HD) units are the main performers in the maintenance and management of HD patients' vascular access, and the cognition degree of their specialized knowledge of vascular access directly affects the quality of vascular access management. However, most of the investigations on the cognition of vascular access knowledge take HD patients as the research subjects, while there are few studies on nurses in HD units as the research subjects. Herein, we explored the knowledge of vascular access among HD unit nurses and its influencing factors, aiming to inform the training of HD unit nurses on vascular access management.Methods: By using a convenience sampling method, we investigated the knowledge of vascular access in terms of basic knowledge, vascular access assessment and arteriovenous fistula (AVF) puncture technique knowledge of dialysis unit nurses who volunteered to engage in hemodialysis clinical nursing for more than 6 months in HD units in Sichuan Province from March 2022 to May 2022. Data were collected on demographic characteristics, hospital nature, the city and region where the hospital is located, the working time of hemodialysis. Analysis of variance was used to analyze the score of vascular access specialist knowledge of HD unit nurses, and multiple linear regression was used to explore the influencing factors of vascular access specialist knowledge of HD unit nurses. Results: A total of 222 nurses in HD units were included. The total score of the knowledge of vascular access was 87.52±13.71 points, of which the basic knowledge scored 3.88±0.60 points, the vascular access assessment scored 3.62±0.65 points, and the AVF puncture techniques scored 3.22±0.71 points. Multiple linear regression analysis showed that longer working years [beta: 0.381, 95% confidence interval (CI): 3.064-7.188, P=0.000], more advanced training [beta: 0.206, 95% CI: 2.817-10.672, P=0.001], and public hospital [beta: 0.138, 95% CI: 0.839-12.342, P=0.025] positively predicted higher knowledge of vascular access scores among HD unit nurses (all P<0.05). Conclusions: The cognitive degree of vascular access specialized knowledge of hemodialysis nurses is affected by different working years, training experience and the nature of the hospital. Nursing managers can develop different training and assessment programs for vascular access specialized knowledge according to different influencing factors.