A method was developed for the simultaneous determination of CS2 and CCl4 at trace level in refined TiCl4 by headspace extraction/gas chromatography-quadrupole mass spectrometry(HS/GC-QMS).The optimal parameters including temperature and time for headspace extraction were explored and finally set to 85 ℃ and 20 min.GC separation was performed on a DB-1 MS capillary column with helium as carrier gas.In MS detection,the peak areas of ions at m/z 76 and m/z 117 were acquired in the scan mode of selected ion monitoring(SIM) for quantitative analysis of CS2 and CCl4,which were consistent with the peak area of ion at m/z 86 using n-C6H14 as the internal standard.The results showed that the calibration curves of CS2 and CCl4 were linear over the concentration range of 20-1 000 nL/L (volume concentration) with correlation coefficients of 0.999 8 for CS2 and 0.999 5 for CCl4，respectively.The lowest quantitation limits (LOQs)for CS2 and CCl4 were both 20 nL/L.The average recoveries of TiCl4 samples at four spiked levels of 20,50,200 and 1 000 nL/L were 102.2% for CS2 and 108.5% for CCl4 ,with RSDs of 1.3%-18.9%.The developed method was successfully applied in the residue analysis of CS2 and CCl4 in the refined TiCl4.The HS/GC-QMS method showed a good application prospect in the quality control of refined TiCl4.