Abstract: A multi-scale model was developed to study the hemodynamic behavior of the cardiovascu-lar and coronary artery system assisted by a catheter pump. The lumped parameter model was established, and the hemodynamic parameters of heart failure patients with coronary stenosis under catheter pump assistance were analyzed macroscopically. The micro-flow characteristics of the system under pathological conditions and catheter pump assistance were studied by using computational fluid dyna-mics（CFD）. The results show that the degree of coronary stenosis and stenotic branches have a significant impact on blood flow, and left main artery stenosis has a greater effect on the rate of blood flow reduction than right coronary artery. The blood flow velocity and wall shear stress increase rapidly in the stenotic region, with the appearance of low flow rate area and turbulence phenomenon increasing with the severity of stenosis. Catheter pump assistance effectively increases coronary blood flow and reduces peak wall shear stress and peak flow velocity on the vessel wall caused by stenosis. In conclusion, catheter pump assistance has a positive effect on hemodynamic parameters in heart failure patients with coronary stenosis, and has certain clinical application value.