Objective: To optimize extraction process of Tripterygium wilfordii. Method: Taking extracting amounts of triptolide and total diterpene lactones as indexes

orthogonal test was adopted to optimize extraction process with extracting time

ethanol concentration and consumption as factors.HPLC was adopted to determine the content of triptolide with mobile phase of methanol-water(45:55) and detection wavelength at 218 nm; UV was employed to determine the content of total diterpene lactones with detection wavelength at 550 nm. Result: Ethanol concentration had significant effect on extracting amount of triptolide

but the other two factors had no significant difference;three factors all had no significant effect on the content of total diterpene lactones.Optimum extraction condition were as follows:reflux extracted thrice with 8 times the amount of 95% ethanol for 2

1

1 h;extracting amounts of triptolide and total diterpene lactones were 4.20

86.64 μg·g-1

respectively. Conclusion: This optimized process was feasible and stable with high extracting efficiency of index components.