Objective To investigate the association between the plasma level of fibrinogen and carotid atherosclerosis(CAS)in patients with ischemic cerebrevascddar disease(ICVD),and the effects intensity of different risk factors on CAS.Methods Carotid intima-media thickness(IMT)was measured by color Doppler uhrasonography in 840 patients with ICVD,including cerebral infarction(ci),transient ischemic attack and insufficient blood-supply of vertebral-basilar artery.According to the results of uhrasonography,the patients were divided into four groups:normal(IMT≤0.9 mm),arterial sclerosis (0.9 mm1.5 mm)and stenosis(stenosis of lumina≥30%).The plasma fibrinogen and other biochemical markers were also detected.The history of hypertension,diabetes,hyperlipemia,smoking,drinking were recorded,and the blood pressure was measured.Results The level of fibrinogen was the highest((3.91±1.05)g/L)in the patients with CI,the difference was significant compared to the patients with TIA((3.45±0.81)S/L,X2=62.812,P<0.01),and so was the prevalence of CAS(77.0%),there was significant difference compared to the patients with TIA(61.8%,X2=9.000,P<0.01).The rate of CAS increased gradually with the quartiles of the fibrinogen(the odds ratios in the 2nd,3rd and 4th quartiles(3.16-3.72 g/L,3.72-4.39 g/L and>4.39 g/L)were 1.80,3.36 and 3.38 respectively,all P≤0.01).There were significant differences of age,fibrinogen,systolic blood pressure,hyperglycaemia and history of diabetes and hypertension between the normal-carotid group and three CAS groups.Multiple logistic regression showed that only the age,fibrinogen and systolic blood pressure significandy influenced on the CAS with the highest risk factor being the fibrinogen.Conclusions In the patients with ICVD,the elevated plasma fibrinogen Was significantly correlated with CAS,and misht play more important role than other traditional risk factors.