Abstract: The conditions of preparing mulberry juice by compound enzymolysis were studied. The pectinase and cellulose were regard as compound object by selecting of enzymes. On the basis of single-factor-test,process parameters of mulberry juice were optimized by combination experiments,with response surface methodology analysis was employed to explore the effect of the ratio of enzyme complex,enzymolysis solution p H,enzymolysis hydrolysis temperature,enzymolysis time on the yield of mulberry syrup. The results showed that the optimal parameters were as follows:the ratio of enzyme complex was 1.0 ∶1.36,enzymolysis p H5.0,enzymolysis temperature 49.5 ℃,enzymolysis time 2.6 h,the juice yield was 86.13%,compared with the pectinase enzyme hydrolysis rate increased by10.92%.