Objective To investigate the relationship between Ambulatory Arterial Stiffness Index (AASI)and kidney damage or carotid endarterectomy damage in hypertension patients.Methods One hundred and forty-nine patients with hypertension but without diabetes or other arteriosclerosis diseases were enrolled.Forty-eight healthy volunteers during the same period were enrolled as control group.All participants'24 h-ambulatory blood pressure monitoring(ABPM),urinary albumin/creatinine ratio(ACR)and IMT were recorded and AASI was calculated.Then the correlation between AASI and ACR or IMT were calculated.Results There were significant differences in the urinary albumin/creatinine ratio(46.34 vs.33.52)(P ＜ 0.05),microalbuminuria incidence(41％ vs.21％),Carotid intima-media thickness([0.90 ±0.21]mm vs.[0.83 ±0.20]mm),abnormal incidence(72％ vs.60％)and AAS1(0.50 ± 0.16 vs.0.42 ± 0.17)(P ＜ 0.01)between the subjects with hypertension and those without.The AASI were positively correlated with ACR and IMT in hypertension patients.Compared with healthy subjects,the AASI were significantly increased in the patients with abnormal CR and IMT(P ＜0.05 、P ＜0.01).Conclusion The AASI were correlated with kidney damage and carotid endarterectomy damage in hypertension patients.