Objective To study the relationship between carotid atherosclerotic plaque and white blood cell(WBC),levels of plasma lipid,fibrinogen(Fib) in the patients with cerebral infarction(CI).Methods 38 patients with CI were examined on carotid arteries using magnetic resonance imagine(MRI) to discover the atherosclerotic plaques and ascertain their stability.WBC,the levels of plasma lipids [including total cholesterol,triglyceride,high density lipoprotein,low density lipoprotein(LDL),lipoprotein(a)] and Fib were detected in CI patients and 31 healthy subjects(normal control group,all subjects were examined carotid arteries with color dopper ultrasonography and no plaques were found)].Results 26 patients with CI(68.4 %) showed carotid plaques and 12 patients with CI(31.6%)did not.Of these,the patients with unstable versus stable plaque were 20(52.6%) versus 6(15.8%) respectively.The levels of plasma Fib in the CI group(including CI without plaque,CI with stable plaque and CI with unstable plaque) were significantly higher than that in the normal control group(all P