The purpose of this study was to develop a new preparation process of ginseng extract with the high concentration of prosapogenin, the specific component in Red ginseng. Chemical transformation from the ginseng saponin glycosides to the prosapogenin was analyzed by the HPLC. The extracts of ginseng leaf and stem were processed at the several treatment conditions of the microwave and vinegar(about 14% acidity). MGLS-20 findings show that the ginseng leaf and stem extracts that had been processed with microwave and vinegar for 20 minutes peaked in the level of ginsenoside $Rg_3$(0.906%). MGLS-25 peaked in the level of ginsenoside $Rg_5$(0.329%) in the ginseng leaf and stem extract processed with microwave and vinegar for 25 minute. And the other kinds of ginseng prosapogenin did not show a higher content.