Abstract: Objective To assess the therapeutic effect of azelnidipine on mild-moderate essential hypertension and its safety. Methods Two hundred and thirty-one patients with mild-moderate hypertension admitted to our hospital from March 2010 to June 2011 were included in this study. After treated with placebos for 2 weeks, they were randomly divided into amlodipine treatment group (n=115) and azelnidipine treatment group (n = 116). Patients in amlodipine treatment group were given 5 - 10 mg amlodipine daily and those in azelnidipine treatment group were given 8 - 16 mg azelnidipine daily for 8 weeks during which their blood pressures at sitting and standing position were measured. Results The diastolic blood pressure of the patients at sitting position was lower than their baseline blood pressure after 8 weeks of treatment (12.94±5.50 mmHg vs 13.56±6.22 mmHg) (1 mmHg = 0.133 kPa). The noninferiority marigin was 3 mmHg in the two groups and their double side 95% lower confidence limit was -0.94 (P = 0.000 0＜0.025). No significant difference was observed in the drug-related advertise events between the two groups and in the heart rate of azelnidipine treatment group after 8 weeks of treatment (P＞0.05). Conclusion Azelnidipine(8 - 16 mg/d) for 8 weeks can significantly reduce the blood pressure of patients with mild -moderate essential hypertension with a good safety and its effect is similar to that of amlodipine (5 - 10 mg/d).