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Chinese herbal medicine（CHM）, as the important part of Chinese medicine legacy, plays an signifiable role in the health of the Chinese. The requirement of CHMs is on the increase, resultingly the cultivation of CHMs is depended on manpower. Because pesticides are applied to a broad variety of CHMs to reduce loss from insects, CHMs have a high risk of contamination of pesticides. It not only affects the quality of Chinese medicinal herbs, but also our exports. Therefore, it is really significant to develop a simple, fast, available and efficient qualitative and quantitative method for measuring pesticide residues in Chinese medicinal herbs so as to ensure the quality and exports of Chinese medicinal herb.Recent years, single residue and selective multi-residue pesticide are the main study, which falls short of the factual contamination in Chinese medicinal herbs.In the present thesis,with the sample pre-treatment by CO2 Supercritical Fluid Extraction （SFE） technology, fast detection protocols on sigle residue and multi-pesticide residues in Gynostemmna pentaphullum were established using Gas Chromatography/ Mass Spectrometry.1. The sigle residue pesticide Metalaxyl was extracted by supercritical fluid extraction （SFE）, purified by alumina chromatography columnand detected by Gas Chromatography/ Mass Spectrometry（GC/MS）. The suit technology conditions was obtained as: firstly static extracting 20 min then turn to dynamic doing, the best dynamic extraction conditions is 31.028MPa, 35℃, dynamic extraction with 40 mL of CO2, and 5 mL of acetone as collecting solvent. Recoveries ranged from 86.58101.87%, and a method precision of 6.3812.75% were obtained for spiking levels of 0.12 mg/kg.2. The sigle residue pesticide Chlorpyrifos was extracted by SFE, purified by florisil chromatography column and detected by GC/MS. The suit technology conditions was obtained as: firstly static extracting 20 min then turn to dynamic doing , the best dynamic extraction conditions is 41.370MPa, 50℃, dynamic extraction with 30 mL of CO2, and 5 mL of acetone as collecting solvent. Recoveries ranged from 88.87 112.32 %, and a method precision of 6.5813.78% were obtained for spiking levels of 0.12 mg/kg. Compareing to the general method SFE technique is simple and convenient, and has the merits of high efficiency accuracy, innocuity, economization, and so on. 3. The multi-residue pyrethroid pesticide of Cyhalothrin, Cyfluthrin, Cypermethrin and Fenvalerate was extracted by SFE, purified by florisil chromatography column and detected by GC/MS. The suit technology conditions was obtained as: pressure 41.370MPa, temperature 45℃, dynamic extraction with 25 mL of CO2,doses of modifier 0.08ml/g（matrix） and static time 25min. Recoveries ranged from 78.53 108.71 %, and a method precision of 6.7111.28% were obtained for spiking levels of 0.12 mg/kg.4. The multi-residue pesticide of Chlorothalonil, Chlorpyrifos, Cyhalothrin and Cypermethrin was extracted by SFE, purified by florisil chromatography column and detected by GC/MS. The suit technology conditions was obtained as: pressure 34.475MPa, temperature 45℃, dynamic extraction with 25 mL of CO2, doses of modifier 0.06ml/g（matrix） and static time 25min. Recoveries ranged from 78.36 110.47 %, and a method precision of 5.6911.45% were obtained for spiking levels of 0.12 mg/kg.5. A method for the determination of 13 pesticide residues was investigated.α-BHC,β-BHC,γ-BHC, Chlorothalonil, Metalaxyl, Parathion-methyl, Chlorpyrifos, PP′-DDT, OP′-DDT, Cyhalothrin, Cyfluthrin, Cypermethrin and Fenvalerate were extracted by SFE, purified by florisi+active carbon chromatography column and detected by GC/MS. The suit technology conditions was obtained as: pressure 41.370MPa, temperature 45℃, dynamic extraction with 25 mL of CO2, doses of modifier 0.06ml/g（matrix） and static time 20min. Recoveries ranged from 74.32 105.93 %, and a method precision of 5.8713.08% were obtained for spiking levels of 0.12 mg/kg. Compareing to the general method SFE technique is simple and convenient, and has the merits of high efficiency accuracy, innocuity, economization, and so on.Detections ensitivity can be significantly increased and interference from impurities can be excluded by using selective ionic monitoringte chnique. The method was proved to be effective and practical. Gynostemmna pentaphullum, Lonicera japonica and Polygonatum sibiricum Redoute which were derived from CHM cultivation place in shaanxi province were detected four pesticide residue, and the amount of residue are all lower than the national standard.In the paper,with the sample pre-treatment by CO2 Supercritical Fluid Extraction （SFE） technology, fast detection protocols on sigle residue and multi-residue pesticides in Gynostemmna pentaphullum were established using Gas Chromatography/Mass Spectrometry. The experiment method is sensitive, accurate and precise. The spiked recovery and RSD fit for the standard of pesticide analysis.
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