Objectives: This study aimed at the cause-effect relations and optimization of Vietnamese Ginseng (Panax vietnamensis Ha et Grushv, Araliaceae) extraction process by heat reflux method based on the extraction yield and the contents of ginsenosid-Rg1 (G-Rg1), majonosid-R2 (M-R2) and ginsenosid-Rb1 (G-Rb1).