Method for preparing sustained-release microgranules

Sustained-release microgranules and a method for preparing same. The method comprises the following steps: 1) preparing a solid dispersion of a water-soluble drug and a biodegradable and biocompatible water-insoluble polymer; 2) dissolving the prepared solid dispersion in an organic solvent to form a solid dispersion emulsion; 3) injecting the obtained solid dispersion emulsion into a surfactant-containing aqueous solution to form a uniform emulsion; and 4) curing microgranules in the emulsion by means of solvent evaporation or solvent extraction, and collecting, washing and drying the microgranules to obtain the sustained-release microgranules. The method for preparing sustained-release microgranules is carried out at normal temperature or low temperature in the whole process, the prepared sustained-release microgranules have an approximate zero-level sustained-release effect, and the drug has a stable concentration in a sustained-release period.