[Objective]To select the optimal extraction technology for the extraction of polysaccharides from black soybean by enzyme hydrolysis method. [Methods] The optimal enzyme was selected among cellulase,pectinase and papain. Effects of extraction temperature,extraction time,pH value and enzyme concentration were investigated. With the extraction rate of polysaccharides in black soybean as the evaluation index,the extraction parameters were optimized by asterion optimization design. [Results]Among the papain,cellulase and pectinase,cellulase showed the maximum extraction rate. The optimal extraction condition was as follows: pH 6. 0,0. 03 mg / mL enzyme concentration,50 ℃ extraction tempeature and 120 min extraction time. [Conclusions]Under the optimal condition,the extraction rate of polysaccharides from black soybean was 0. 321 4%,which had 99. 41% degree of closeness to the theoretical value. Factors affecting the extraction rate of polysaccharides from black soybean were in the order of pH value > extraction time > extraction tempeature. [Methods] The optimal enzyme was selected among cellulase, pectinase and papain. Effects of extraction temperature, extraction time, pH value and enzyme concentration were investigated. With the extraction rate of polysaccharides in black soybean as the evaluation index, the extraction parameters were optimized by asterio optimization design. [Results] Among the papain, cellulase and pectinase, cellulase showed the maximum extraction rate. The optimal extraction condition was As follows: pH 6. 0,0. 03 mg / mL enzyme concentration, 50 ° C extraction tempeature and 120 min extraction time. [Conclusions] Under the optimal condition, the extraction rate of polysaccharides from black soybean was 0. 321 4% which had 99. 41% degree of closeness to the theoretical value. Factors affecting the extraction rate of polysaccharides from black soybean were in the order of pH value> extraction time> extraction tempeature.