Abstract: The aim of this study was to evaluate the efficacy and tolerance of allo. comp. ratiopharm on lowering serum uric acid in patients with gout or hyperuricemia by a prospective, double blind, comparative clinical trial. Thirty four patients with gout or hyperuricemia randomly took one tablet of allo. comp. （containing 100mg allopurinol and 20mg benzbromarone） or 100mg allopurinol daily for 2 weeks. It was found that the mean decrease of serum uric acid in allo. comp. group （n=22） was significently greater than that in allopurinol group （n=12, P ＜0.01）, whereas, the mean reduction of urinary uric acid excretion in allo. comp. group was significantly less than that in allopurinol group. The results suggested that allo. comp had stronger efficacy on lowering serum uric acid. Serere side effects were not found in patients taking allo. comp.