A quantitative analysis of seven components of 17-KS in human urine was successfully carried out by GC-MS. The sample including deuterated 17-KS was introduced into TMS derivatives by BSTFA in pyridine. The derived TMS derivatives were analysed using the GC-MS system equipped with the column of 0.5% NPGS Chromosorb W AW DMCS, and the temperature was programmed from 180°C to 240°C at 3°C/min. increment. Seven components were well separated, and each fraction was analysed by MS spectrum. Normal human urine was analysed by this method, the result of which is summarized in Table 3.