OBJECTIVE To study the relationship between carotid atherosclerosis and cerebral infarction (CI). METHODS Between November 2008 and March 2009, 147 CI patients (CI group) and 48 patients with non-cerebrovascular diseases (control group) were enrolled from inpatients of Neurology Department of our hospital. The diagnostic criterion of thickened carotid intima was set as 1.0 mm<intima-media thickness (IMT) < 1.5 mm and that of carotid plaque was as IMT 1.5 mm. Carotid atherosclerosis was divided into three levels: normal intima, thickened intima, and plaque formation. The color Doppler ultrasonography data of carotid arteries in all patients were analyzed and the severity of carotid atherosclerosis was compared between the two groups. RESULTS In the CI group, 36 (24.5%) patients had normal carotid intima, 22 (15.0%) had thickened carotid intima, and 89 (60.5%) had carotid plaque. In the control group, 22 (45.8%) patients had normal carotid intima, 4 (8.3%) had thickened carotid intima, and 22 (45.8%) had carotid plaque. The severity of carotid atherosclerosis in the CI group was higher than that in the control group (P = 0.022). There was significant difference in the constitution of carotid plaque between the two groups (P = 0.001); the CI group mainly had the soft plaque (55/89, 61.8%), whereas the control group mainly had the hard plaque (17/22, 77.3%). The first three common locations of carotid plaque in both groups were carotid bifurcation (CI group: 73.7%; control group: 64.1%), common carotid artery (CI group: 20.4%; control group: 25.6%), and internal carotid artery (CI group: 5.9%; control group: 10.3%). The location of carotid plaque between the two groups was not significantly different (P = 0.438). There was no difference in the carotid inner diameter or resistance index between the two groups (P > 0.05). CONCLUSIONS Carotid atherosclerosis is to some extent able to reveal the atherosclerotic condition of cerebral arteries and act as an important predictor for the risk of CI. The color Doppler ultrasonography of carotid arteries can provide a convenient way for the prevention and treatment of CI.