Objective To observe the thrombolytic effects of urokinase in the treatment of thrombosed hemodialysis autologous arteriovenous fistulae and to analyze the factors influencing the effects. Methods Urokinase was injected into the thrombosed fistulae with the dose of 50000～500000u. Before and after treatment, the color Doppler ultrasonography was performed to examine the fistulae. The hepatic and renal function, prothrombin time and the plasma fibrinogen were detected, and the blood pressure was measured. The side effects were also observed. Results Of the total 50 treatment, 43(86%) were successful. In the successful cases, the proportion of male and climacteric female patients was higher than that in the unsuccessful cases. The thrombosis time of the successful cases was shorter. And the proportion of the patients who were suffered from thrombophlebitis was higher in the unsuccessful cases. No bleeding and embolism complication were observed. Conclusion The thrombolytic treatment using urokinase is an effective method in thrombosed hemodialysis autologous arteriovenous fistulae. But the effect may unsatisfactory in female and patients whose thrombosis time was longer or who were suffered from thrombophlebitis.