Objective To investigate the effects of different degrees of left anterior descending (LAD) stenosis and bifurcation vessel curvature on hemodynamics. Methods An ideal model with different bifurcation radii of curvature and stenosis rates of LAD branches was developed. The effects from different radii of curvature and different stenosis rates on blood flow and wall shear stress (WSS)-related parameters were evaluated using the fluid-structure interaction (FSI) method. Results After stenosis occurred at the LAD, the regions of high oscillatory shear index (OSI) and high relative residence time (RRT) were mainly distributed on contralateral sides of the LAD bifurcation ridge, proximal downstream of the stenosis location at lateral sides of the bend, and distal downstream at medial sides of the bend. And with the increase of the degree of stenosis, such areas and degrees would be expanded. As the radius of curvature decreased, high OSI and RRT in medial side of the bend were distributed distally at downstream of the LAD, and the average decrease of high RRT area relative to the whole vascular area could reach 35.68%. With the increase of the stenosis degree Conclusions The presence of LAD stenosis increases the risks of secondary stenosis at downstream of the stenosis location and contralateral side of the LAD bifurcation ridge. The decrease in curvature promotes the formation and development of plaque at medial side of the bend. Still, it will decrease the probability of plaque formation for the entire vessel. The results may provide the theoretical reference for protocol design and optimization for treating LAD lesions and preventing secondary stenosis.