A GC method for the residue of Hexachorocyclohexane,Dicophanum,Dimethoate and Parathionun in Ginkgo Biloba extract is reported.The linear range of α-BHC,-BHC,β-BHC,δ-BHC,pp-DDE,op-DDT,pp-DDD and pp-DDT is 0.008～0.056 μg/ml,0.01～0.050 μg/ml,0.008～0.056 μg/ml,0.01～0.07 μg/ml,0.004～0.028 μg/ml,0.008～0.056 μg/ml,0.008～0.056 μg/ml and 0.008～0.056 μg/ml,and Dimethoate,Parathionun is 12.0～40.0 μg/ml and 6.0～20.0 μg/ml,rspectively.The average recovery of α-BHC,-BHC,β-BHC,δ-BHC,pp-DDE,op-DDT,pp-DDD and pp-DDT is 82.94%,88.46%,89.09%,93.68%,90.31%,86.45% and 92.52%,and that of Dimethoate and Parathionun is 09.58% and 91.42%,respectively.
