The optimization of the conversion of ginseng saponin glycosides to 20(S)-ginsenoside Rg(3) by enzymatic transformation was carried out using response surface methodology (RSM) based on a 2(3) factorial central composite design. The production of 20(S)-ginsenoside Rg(3) using several commercial enzymes indicated that the enzyme Cellulase-12T was the most efficient at producing 20(S)-ginsenoside Rg(3). To optimize the enzymatic production of 20(S)-ginsenoside Rg(3), response surface methodology was applied to determine the ideal amount of white ginseng extract, Cellulase-12T and reaction time. These results indicate that white ginseng extract (1.67%) treated with Celluase-12T (3.67%) for 72 hours had 4 times the quantity of 20(S)-ginsenoside Rg(3) compared to commercial white ginseng extract.