OBJECTIVE To evaluate the effectiveness and safety of L-amlodipine besylate for blood pressure control in patients with mild to moderate essential hypertension. METHODS A total of 1051 mild to moderate essential hypertensives were recruited from 22 centers and randomized into three groups and were given low-dose L-amlodipine besylate (2.5 mg/d), high-dose L-amlodipine besylate (5.0 mg/d), and amlodipine maleate (5.0 mg/d) on the principle of open-label and parallel control. The study drugs were administered for 8 weeks. RESULTS After 8 weeks treatments, the response rate of the three groups were 72.4%, 85.6%, and 76.2%, respectively. The rate difference between high-dose L-amlodipine besylate group and the other two groups were statistically significant (P < 0.01), while the rate difference between low-dose L-amlodipine besylate group and amlodipine maleate group was similar (P = 0.28). The event rates of the three groups were similar (4.3%, 4.6%, and 5.1%, respectively, P = 0.84). CONCLUSIONS High-dose L-amlodipine besylate is superior to the other 2 groups on blood pressure control. The efficacy profiles of amlodipine maleate and low-dose L-amlodipine besylate are equivalent. Safety profiles of these three groups are comparable.