Abstract: Enhancement of asymmetric reduction efficiency for (R)-mandelic acid (MA) from phenylglyoxylic acid (PGA) was investigated with whole cells of Saccharomyces ellipsoideus as catalyst. Utilization of fed-batch and addition of adsorbent resin could be effective in increasing substrate concentration and mitigating substrate inhibition. Absorbent resin NKAⅡ was selected，which had a large adsorption amount and a high adsorption rate of the substrate. By adding NKAⅡ adsorption resin in the reaction system，substrate inhibition was mitigated，and the initial substrate concentration was thus increased. Finally it was found that combining these two methods was the most effective way. Substrate concentration was increased from 33.31 mmol/L to 166.53 mmol/L, and a 95.6% yield of (R)-mandelic was obtained with fed-batch in a resin-added system. Reusability of cell was satisfactory.