Effects on polysaccharide yield of enzyme digestion with different concentrations of pectinase,cellulase,laccase at fixed substrate concentration(1∶ 15) and reaction temperature(40℃) were investigated.Based on results from university test,response surface method was applied to establish the quadratic polynomial model and the validity was verified.Interactions among these three factors of pectinase,cellulase,laccase and their optimal level were discussed.Results of response surface analysis showed that: pectinase,cellulase,laccase significantly affects lentinan yield independently and a 37.07% extraction ratio of lentinan was achieved with the optimized concentration of three enzyme at 7.11%,6.82% and 3.69%,respectively.