The invention discloses a method for the enzymatic synthesis of cefprozil in a recyclable aqueous two-phase system by using immobilized penicillin acylase. The method comprises the following steps: dissolving a cefprozil parent nucleus and an acylation reagent in an aqueous two-phase polymer solution, wherein the molar ratio of the parent nucleus to the acylation reagent is 1: (1-4); and adding immobilized penicillin G acylase, then adding a two-phase distribution conditioning agent, adjusting the pH value to 4.5-7, and reacting for 1 to 80 hours at the temperature of 5-30 DEG C, wherein the concentration of enzyme in a reaction system is 50-150U / ml. By adopting the method, the hydrolytic activity of the penicillin acylase can be effectively inhibited, thus the hydrolysis degrees of the acylation reagent and the cefprozil product can be reduced. Compared with a method using water as a medium, the method disclosed by the invention has the advantages that the product and the enzyme are distributed in two different water phases, a reactant is fully in contact with the enzyme, so that a synthesis / hydrolysis specific value is greatly increased, the yield of the cefprozil can be increased by 20%, and the highest yield can reach 78%; the adopted novel recyclable aqueous two-phase system can be recycled, so that the production cost is reduced.