Objective To study the hemodynamic characteristics after vascular drug eluting stent (DES) implantation, so as to provide theoretical guidance for clinical application of DES as well as improving the design of DES. Methods The geometry models of vascular lesions implanted with DES were constructed to numerically analyze drug concentration and wall shear stress (WSS) distributions in vessel by computational fluid dynamics (CFD) method. The results were compared with flow characteristics of the model with bare metal stent (BMS) implantation. Results Low WSS accompanied by high drug concentration would occur during blood flow in some areas after DES implantation, and vice versa. The presence of DES significantly reduced appearing such areas as either with low WSS only or with low drug concentration only. Theoretically, DES had more advantages than BMS at the stage of drug release. Conclusions DES could dramatically reduce the ratio of in-stent restenosis. Understanding the regular pattern of blood flow field distributions after DES implantation in detail will be beneficial to improve the design of DES, and further advance the overall performance of the stent, which can provide the theoretical basis for clinical research.