In this study, the bioconversion of soybean extract was performed using various enzymes, and then the change of biological activity before and after the bioconversion was characterized. Embryo bud of soybean was firstly extracted using hot water and then extracted again using 95% ethanol, which was named as isoflavone rich soybean extract(IRSE), and this was used for the bioconversion experiments. The bioconversion of IRSE was performed using β-glucosidase, Novozym or Accellerase, which are commercial enzymes. The change of composition of the IRSE before and after the bioconversion was determined using HPLC. The major components of IRSE were genistin and daidzin, which are the glucosides, and genistein and daidzein, which are the aglycones. After 24 hours bioconversionprocess, the major part of genistin and daidzin was converted into genistein or daidzein. The anti-oxidant activities of IRSE were determined before and after bioconversion. The bioconversion process did not influence significantly on the anti-oxidant activities of IRSE. On the other hand, various biological activities were also determined before and after the bioconversion using RAW 264.7 cell. The experimental results showed that both the NO generations in RAW 264.7 effectively after the bioconversion. Taken all together, we could conclude that the bioconversion of IRSE may be useful to the preparation for enhanced functional cosmetic raw materials using soybean extract.