Abstract: Determination of Codeine and its Metabolite in Urine by GC/MSCul Kairong; Wu Yun; Wang Shan;Xu Youxuan; Sheng Li; Zhang Changjitu(National Research institute of Sports Medicine, Beijing, 100029, China)Abstract:A GC/MSD and SIM Method for determination of codeine and its metabolite in human urine was developed. Satisfactory linearities of calibration curves were obtainedwithin the range designed in the paper. The method can be used to determine codeineand its metabolite doping control.Keywords: Codeine, Morphine, Selected ion Monitoring (SIM), GC/MSD