OBJECTIVE:To prepare multivesicular liposomes-sodium polymannuronate microspheres(MVLs-Alg)for protein drugs and to study the physico-chemical property and elementary stability of MVLs-Alg.METHODS:MVLs and Alg were used as matrix and BSA as a model protein drug,MVLs-Alg microspheres were prepared by interior/gelatin method.The relationship between MVLs and Alg was analyzed by differential thermal analysis and the effect of temperature(4,25,40 ℃)on entrapment efficiency and peroxide value of phospholipid in base material was investigated.RESULTS:The MVLs-Alg microspheres were spherical.Analyzed by DTA,it was considered that physical adsorption between MVLs and Alg was potentially existed.Storing for 90 days at 4,25,and 40 ℃ respectively,the encapsulation efficiency of the MVLs-Alg microsphereswere were 85.36%,63.75%,and 50.49%,respectively.The peroxide value of phospholipid increased increasingly,but not significant as compared with MVLs.CONCLUSIONS:The stability of MVLs-Alg microspheres was heightened compared with that of MVLs and which can be used for the delivery of protein drugs.