Abstract: Objective To study the intima-media thickness (IMT), plaque score in the carotid artery of patients with acute coronary syndrome (ACS) and the relationship between high-sensitivity C-reactive protein (hs-CRP) and the plaque score. Methods Using high-resolution ultrasonic instrument, IMT and the plaque score in the carotid artery were detected in 30 patients with ACS, 29 patients with stable angina pectoris(SAP) and 17 control subjects, in addition to the measurement of hs-CRP. Results Compared with SAP and control groups, IMT, total plaque score, soft and hard plaque scores in the carotid artery in ACS group were significantly increased (P<0.001). Hs-CRP (4.336±1.334 mg/L) in ACS group were significantly increased (P<0.001) as compared with that in SAP group (2.205±0.458 mg/L) and control group (1.625±0.434 mg/L). Hs-CRP had positive relationship with the IMT, whole plaque score, soft and hard plaque scores in the carotid artery, respectively. Conclusion IMT, total plaque score, soft and hard plaque scores in the carotid artery in ACS group are significantly increased, and hs-CRP is positively related to IMT, total plaque score, soft and hard plaque scores in the carotid artery, respectively.