Abstract: In order to investigate the hypouricemic function of ethanol extracts from eucalyptus leaves on hogs，the ethanol extracts were extracted from eucalyptus leaves using continuous phase transition extraction apparatus. The main ingredients of extracts were analyzed using high performance liquid chromatography（HPLC），and its effects on the uric acid in serum and urine of hogs were studied. The results showed that the extracts had no effect on the uric acid in serum，but the 1.2 g/kg dose group of extracts significantly promoted the excretion of uric acid in urine.