Aim To demonstrate the relationship between stenosis degree as well as plaque morphology and cerebral ischemia. Methods The inner carotid arteries of 10 patients with cerebral ischemia before death were removed en block in autopsy. After fixation, the arteries were serially cut into blocks in an interval of 4 mm and HE sections were made from every block. The HE sections were microscopically observed and the lumen area and lipid core area were measured through computer image analysis system. 10 control cases without cerebral ischemia before death were also studied, the study method and measured parameters were similar to the cerebral ischemia groups. Results Among the total 151 blocks in cerebral ischemia group, the lumen area was 6.2 mm 2 in maximum and 3.2 mm 2 in minimum, the average was 4.7±0.3 mm 2. In control group, the maximum and mimimum lumen area was 6.5 and 3.6 mm 2, with an average of 4.8±0.4 mm 2. There was no significant difference between the two groups. While the average lipid core area in cerebral ischemia group and control group was 3.4±0.4 and 1.8±0.2 mm 2 respectively. The difference was significant (p<0.01). In addition, 11 thromboli were found in the cerebral ischemia group, but no thrombus was found in the control group. Conclusion there was no significant difference of stenosis between cerebral ischemia and control groups, but the lipid core area in cerebral ischemia group was larger than that of control group. The stenosis degree may not take a more great role in the occurrence of cerebral ischemia than the lipid core size does.