Abstract: To prepare lysozyme loaded microspheres with excellent properties for resolving the problem of degradation rate of chitosan in vivo，the preparation and characterization of lysozyme loaded microspheres were investigated from different angles systemically. The results showed that the yield was between 5.7% and 97.4%，the diameter was from 30µm to 100µm，the drug loading and the encapsulation efficiency were both ideal. Furthermore，the controlled release efficacy was obvious，the cumulative release ratio ranged from 20% to 70% in 16 days，which matched the first order kinetic model. Most importantly，the enzyme maintained its specific activity at above 90%.