Decompressing inner ebullition extraction (DIEE) [1,2] is a novel method to extract active components from plants.In this method,a small volume of release-solvent with a comparatively low boiling point is used to saturate the plant.Subsequently,a hot solvent with a higher boiling point is added at a higher temperature and in a much larger amount.At the same time,the pressure of extraction is decompressed rapidly.As a result,the release-solvent inside the plant is heated to boiling and the mass transfer is intensified.In this study,DIEE is used to extract Panax Notoginseng Saponins from Panax Notoginseng [3,4].The optimal extraction conditions and the curses of extraction kinetics are determined by experiment.The present research shows that,compared to the ultrasound-assisted extraction (UAE) [5-7],the DIEE gives the same yields within very short times.The detailed results are showed as followings:when the operation gauge pressure is-0.084 MPa,the mass concentration of ethanol saturated the material is 50% and the volume of water is 10 times to mass of Panax Notoginseng cells,the extraction process finished within 30 s.According to the results of the fitting kinetics equations,both DIEE and UAE can accord with the model of unsteady diffusion.The mass transfer coefficients of DIEE are between 0.08 and 0.13 s-1,which are 100 times faster than that of UAE.The activation energy of the extraction process is between 11 and 16 KJ.This study provides a high effective and feasible method for èxtraction of Chinese medicine.