Abstract: Objective: To study the correlation between the macrophages apoptosis and the vulnerability of atherosclerotic plaque.Methods: 8 male new Zealand white rabbits were made the atherosclerotic model.The rabbits were euthanized.The entire length of the aorta was exposed and was divided several segments.Then histological assessment of experimental atherosclerosis,immunohistochemical staining for macrophages,and apoptosis detection were performed.At last,statistical analysis was made.Results: The statistical analyses showed that the fibrous cap thickness were significantly inversely correlated with macrophages burden（r=-0.782,P=0.001）.And the ratio of fibrous cap thickness and nucleus thickness was more significantly inversely correlated with macrophages burden（r=-0.943,P＜0.001）.Conclusion: The present study demonstrates the macrophages apoptosis can affect the vulnerability of atherosclerotic plaque and make the plaque instable.