This is a multicenter, randomized, double-blind, parallel-controlled study, conducted in Chinese patients with mild to moderate essential hypertension. After a 2-week washout period, 236 eligible patients were randomly to receive aranidipine 5-10 mg/d (n = 118) or amlodipine 5-10 mg/d (n = 118) for 10 weeks. The blood pressure and heart rate were evaluated in outpatient clinics, and ambulatory blood pressure monitoring was performed in 24 patients in each group. The blood pressure was significantly decreased in both groups. Compared with amlodipine, the patients who received aranidipine had less response in blood pressure (P < 0.01). The trough/peak ratios of diastolic blood pressure in aranidipine and amlodipine groups were 0.57 ± 0.20 and 0.68 ± 0.19, respectively (P = 0.119). Adverse events occurred at 11.86% and 7.63% in the aranidipine and amlodipine groups, respectively (P = 0.348). Headache was observed at an incidence of >3.0% in both groups, and the serum glucose and lipid profile had no significant change in the amlodipine group. In conclusion, once-daily administration of aranidipine (5-10 mg) effectively controlled blood pressure, and the short-term treatment might result in it being less effective than amlodipine. It had a stable action over 24-hour period, and the mechanism of that is not yet clear. Aranidipine had a good safety similar to that of amlodipine.