Objective:To establish a method for determining sulfide in the hydrogen sulfide poisoned blood using gas chromatograph-mass spectrometry(GC/MS) and to apply this method in reality. Methods:Different types of sulfides in poisoned blood were converted into sulfur ions by benzalkonium chloride and disodium tetraborate decahydrate mixed solution in alkaline medium. The target analytes were reacted with pentafluorobenzyl bromide(PFBBr) for derivatization. 1,3,5-tribromobenzene(TBB) was used as internal standard. The derivatives of sulfides were extracted by liquid-liquid solvent extraction and were analyzed by GC/MS. Data were acquired in the selected ion monitoring(SIM) mode and the quantitation of sulfide was done by using internal standard method. Results:A good linearity was obtained at the concentration range of 0.05-10.0 μmol/ml in blood sample,with the correlation coefficient of 0.997 2. The lowest limit of detection was 0.007 2 μmol/ml. Conclusions:The established method is proved to be sensitive,simple,specific and accurate. It can be applied in the quick detection of sulfides in the hydrogen sulfide poisoned blood in medicolegal identification and clinical laboratory.