Objective The influence of plaque classification and bifurcation angle on hemodynamics in coronary artery was analyzed, and the effect on vulnerable atherosclerotic plaques was further discussed. Methods Based on the average geometric parameters of human coronary artery bifurcation vessels, a three-dimensional model of fluid-solid interaction for coronary bifurcation vessels with different plaque classifications and vessel bifurcation angles was constructed in this study to investigate the blood flow velocity, pressure and shear stress distribution at the critical areas. Results The upstream shoulder of the plaque is the site with the highest shear stress on the plaque surface, which is prone to ulceration or rupture and further growth. When there are plaques on one side of the bifurcation vessels, the shear stress of the carina of bifurcations is greater than that of the bilateral plaques. The pressure and shear stress at the carina of the bifurcation of vessels gradually increase as the bifurcation angle decreases. Conclusions When there are plaques on one side of the bifurcation vessels, the probability of damage is greater than that of the bilateral plaques. The presence of plaque in main vessels can promote the formation and growth of plaque at the bifurcation plaque. The inner wall of the blood vessels at the carina of the bifurcation is more easily damaged in the case of small angle vessels. The research results can provide theoretical references for the treatment of vulnerable atherosclerotic plaque.