Abstract: A new method of GC/MS coupled with accelerated solvent extraction(ASE) to determined methcathinone in blood sample is developed. Methcathinone were extracted by the ASE method using optimized parameters(solvent, temperature and time), the concentrated eluate was analyzed with GC/MS.The detection limit of the method is 0.02 mg/L, and the quantitative limit is 0.1 mg/L. The recoveries of methcathinone with three added levels in the blood were 96.70%~99.27%. A good linear relationship was obtained at the range of 0.1~50 mg/L. The method is rapid, simple, convenient and effective, and the proposed method can be used to extract methcathinone in biological specimens due to its superiority comparing with other traditional extraction methods.