Abstract: Objective: To investigate the changes of the plasma fibrinolytic activites and serum homocysteine concentrations in patients with the carotid atherosclerosis. Methods: Blood samples were collected from 98 patients with the carotid atherosclerosis and 94 controls. t-PA and PAI-1 activities were determinated by chromogenic substrate assay, Hcy concentrations by fluorescence polarization immunoassay. Results: Plasma PAI-1 activites and serum homocysteine concentrations were higher and t-PA activities were lower significantly in patients with the carotid atherosclerosis than those in controls（P＜0.05）. Multivariate logistic regression model indicated that smoking, hypertension, low fibrinolytic activities, hyperhomocysteinemia, hypercholesterolemia were associated with the carotid atherosclerosis. Conclusion: Low fibrinolytic activities and hyperhomocysteinemia may be the risk factors of the carotid atherosclerosis.