Objectives: Stenosis caused by intimal hyperplasia is the main reason of arteriovenous fistula(AVF) dysfunction. In recent years, it is believed that AVF established by functional end-to-side anastomosis can reduce the intimal hyperplasia and improve patency rate. This paper intends to explore the possible mechanism of functional end-to-side anastomosis improving the intimal hyperplasia of AVF from the perspective of hemodynamics. Methods: AVF models of functional end-to-side anastomosis (STE) and conventional end-to-side anastomosis (cSTE) were established by SolidWorks 2018. Models were meshed by Anasys-meshing 2017. Fluent.17 was used to simulate the hemodynamics of each model with blood flow velocity, pressure drop, low wall shear stress area (LWSSA). Results:Retrograde flow: flow velocity, STE 31.84cm/s, CSTE 31.76cm/s; pressure drop, STE - 194.63pa, CSTE - 196.62pa; The total LWSSA in STE was 5.70% lower than CSTE (61.31 vs 64.91mm2); The effective LWSSA in STE was 78.87% lower than CSTE (3.74 vs 17.70mm2). Antegrade flow: flow velocity, STE 25.74cm/s, CSTE 25.58cm/s; pressure drop, STE -108.02pa, CSTE -143.69pa;The total LWSSA in STE was 6.97% greater than CSTE (42.35 vs 39.59mm2);The effective LWSSA in STE was 10.62% lower than CSTE (1.01 vs 1.31mm2). Conclusions: In retrograde flow state, functional end-to-side anastomosis can significantly improve the hemodynamics of AVF without affecting the flow velocity of outflow tract, while in antegrade flow state, functional end-to-side anastomosis has no significant effect on the hemodynamics of AVF.