Abstract: A Metabolite of dihydrotestosterone was found in its volunteer urine by GC/MSD. According to the main metabolic pathways of anabolic steroids drugs and the mass spectrum data obtained from urinary extract, the structure of the metabolite was deducted 16-hydroxy dihydrotestosterone. This metabolite can be detected in the urine within 24 hours after the drug administered. The detection of 16-hydroxy dihydrotestosterone can be used in doping testing to control the abuse of dihydrotestostrone.