Hypoparathyroidism (HypoPT) is one of the most common complications after thyroid surgery. The parathyroid hormone-controlled delivery system is one of the most significant therapies for hypothyroidism after thyroid and parathyroid surgery. The character of biodegradability and the slow release of PTH of the Sustained release microspheres were widely concerned. The authors present the research progress in sustained release microspheres loaded with PTH from the character, material, fabrication and application. 2 Sustained release microsphere 2.1 Character The material of microspheres should meet the following requirements[7]: 1)Satisfactory biocompatibility, including blood compatibility, histocompatibility and nonimmunogenicit. Moreover, non-poisonous and non-teratogenic, Products after degradation have no