Aim To discuss the relevance between cerebral infarction and carotid atherosclerotic plaque.Methods 47 patients with cerebral infarction were tested by ultrasound,and the site,nature and artery lumen diameter of their plaque were observed and compared with the result detected from 39 patients suffering carotid artery atherosclerotic plaque of the comparative group.Results The carotid artery atherosclerotic plaque of patients with cerebral infarction are mostly unstable plaques and associated with lipid levels(P<0.05),the distribution of carotid atherosclerotic plaque are mostly at the BIF.Conclusions The occurrence of cerebral infarction is closely related to carotid atherosclerotic plaque,the nature and distribution of carotid atherosclerotic plaque has something to do with the lipid levels.Through ultrasonic inspection we can detect the formation of plaque at an early stage,which is critical to the prevention of the occurrence of cerebral infarction.