Abstract: Objective A sensitive and accurate High Resolution Gas Chromatography/High Resolution Mass Spectrometry(HRGC/HRMS)method was developed for determinating seventeen Polychlorinated Dibenzo-p-Dioxins and Dibenzo-Furans in saled milk using isotope dilution quantitation technique.Methods Dibenzo-p-Dioxins and Dibenzo-Furans was extracted from milk by liquid-liquid extraction,carbon column enrichment,chromatograph column cleaning up,separation,and followed by HRGC/HRMS-MID determination and quantitation in ppt(pg/g)level.Results The method Detection Limit for TCDF and TCDD is 0.022 2pg/μl and 0.031 7pg/μl respectively.The recovery was 58.46%-79.99%,1,2,3,7,8-PeCDF,1,2,3,4,7,8,9-HpCDF,2,3,7,8-TCDD was non-detection,concentration of OCDF and OCCD were 0.065pg/g and 0.202pg/g in the sample respectively among all the seventeen Dioxins and Furan,and Total Toxicity Equivalency Factor(TEQ) was 0.033pg TEQ/g.Conclusion HRGC/HRMS and method of isotope dilution had the characteristics of quality,accurate quantative,high sensitvity in determinating dioxins of matrix.