Abstract： Objective To investigate carotid intima-media thickness and arterioles atherosclerosis in patients with prehypertension by using high-frequency ultrasound.Methods A total of 1162 healthy controls and 590 prehypertensive patients were enrolled in this investigation.High-frequency ultrasound was used to measure intima-media thickness and evaluate plaque score of the carotid artery.Results In comparison with the healthy controls,the incidence of carotid atherosclerotic plaque and the intima-media thickness of the prehypertensive patients were significantly increased.The detection rate of carotid atherosclerotic plaque was 45.3％ in prehypertensive subjects.In addition,mild,moderate or calcified plaque was found in 68.9％,24.6％ and 6.5％ patients,respectively.Conclusion High frequency ultrasound could accurately evaluate intima-media thickness and atherosclerotic plaque of the carotid artery,which may be conductive to identify high-risk prehypertensive populations.