Objective To explore the hemodynamic characteristics in functional side-to-end (STE) anastomosis arteriovenous fistula (AVF) by computational fluid dynamics (CFD), so as to provide theoretical basis for clinical application of the AVF. Methods AVF models of functional STE anastomosis (STE group) and conventional STE anastomosis (cSTE group) were established. The hemodynamic parameters of models in two groups under retrograde and antegrade flow states were analyzed, including blood flow velocity, pressure drop, low wall shear stress area (LWSSA). Results Under retrograde flow, the total LWSSA in STE group was 5.70% lower than that in cSTE group, and the LWSSA on venous wall in STE group was 49.71% lower than that in cSTE group. Under antegrade flow, the total LWSSA in STE group was 6.97% greater than that in cSTE group, and the LWSSA on venous wall in STE group was 10.62% lower than that in cSTE group. Conclusions Under retrograde flow state, functional STE anastomosis can significantly decrease the LWSSA of AVF, while under antegrade flwo state, functional STE anastomosis has no significant impact on improving the LWSSA of AVF.