Objective:To evaluate the antihypertensive effects of acupuncture in patients with mild-to-moderate essential hypertension by 24 hour ambulatory blood pressure monitoring. Methods:Fifty patients with mild-to-moderate essential hypertension were treated with telmisartan 80mg,once a day for 4 weeks. 24 h ambulatory blood pressure monitoring( ABPM) was performed before and affter treatment the trough/peak ratio and smoothness index were calculated. Results:The mean systolic blood pressure ( SBP) and diastolic blood pressure( DBP) in 24h,day time and nighttime allhad a significantreduction( P 0.05). The blood pressure loads of SBP and DBP were decreased significantly also( P 0. 05). The trough/peak ratio of SBP was76% ,DBP was 72%. The Smooth-ness index of SBP was ( 1. 34 ± 0. 13) ,The Smooth-ness index of DBP was ( 1. 16 ± 0. 22). Conclusion:The compound telmisartan is an effective and safe antihypertensive drug with satisfactory trough/peak ratio and smoothness index.