OBJECTIVE:To study the metabolite and excretion of polydatin (Trans-resveratrol-3-O-glucoside,TRG) and its metabolites in Beagle dog feces,and provide experimental basis for the new drug development of TRG. METHODS:4 Beagle dogs were intragastrically administrated TRG 20％ polyethylene glycol 400 solution 50 mg/kg. LC/MS was used to identify the me-tabolites of TRG in dog feces after 12-24 h of administration,and HPLC was adopted to determine the cumulative excretion rate and excretion speed rate of the major metabolite resveratrol(TR)in feces samples after 0-12,12-24,24-36,36-48,48-72,72-96 h of administration. RESULTS:TR and two sulfate conjugates of TR were found in dog feces,and TR was a major metabolite, while TRG was undetermined. The excretion speed rate of TR in dog feces was the rapidest after 12-24 h of administration,reach-ing 9.65 mg/h. Its cumulative excretion rate was 39.3％,equivalent to 67.2％ of TRG. CONCLUSIONS:After TRG is intragastri-cally administrated to dogs,TRG was mainly excreted in the form of TR via dog feces.