AIM: To observe the efficacy of lansoprazole in treating peptic ulcer in comparison with omeprazole. METHODS: Patients (n=64) with peptic ulcer were divided randomly into 2 groups: 36 patients (M 28, F 8, age 41±s 8 a) in treatment group received lansoprazole 30 mg, po, qm for 4 wk; 28 patients (M 22, F 6, age 42±10 a) as control received omeprazole 20 mg, po, qm for 4 wk. RESULTS: No significant differences in the total response rates(94%vs 93%), ulcer healing rate (89%vs 90%) and the pain relief on d 7 (97%vs96%) were found between in the treatment and control groups (P0.05, respectively). The pain relief rates on d 3 in the treatment group showed better ef_ fect than those in the control(83% vs 71%, P 0.05). The adverse reactions in 2 groups were mild. CONCLUSION: Lansoprazole has a excellent therapeutic effect on peptic ulcer.