Abstract: The flow fields in a 70%-area occluded artery with a complete bypass graft are investigated numerically in the present paper. The major focus is to exploit the effects of the anastomotic angle on the flow fields. Three different anastomotic angles, including 45-, 60- and 75-deg cases are calculated and analyzed, from which it is found that the flow features in both of the stenosed host artery and the bypass graft, including the recirculation structures, secondary flow motions, the percentage of mass flow rate flowing into the bypass graft, and the shear stress distributions on arterial walls, are all closely connected with the anastomotic angle. The information provided in the present paper is helpful for the further understanding of the real aetiology causing the intimal hyperplasia. [Copyright &y& Elsevier]