Abstract: Disclosed are biodegradable microspheres, capable of releasing a glucose-regulating peptide in a controlled manner, comprising a biodegradable polymer carrier with the glucose-regulating peptide encapsulated therein, and methods for the preparation thereof. In addition to ensuring high encapsulation efficiency and high stability of the encapsulated drug, the microspheres shows neither an initial burst effect nor incomplete release and allows the zero-order release of drugs over a prolonged period of time, thus improving the therapeutic effect of the drug.