The present invention relates to a method for preparing microsphere and microspheres produced thereby. The method comprises: mixing a water-insoluble organic solvent with a dispersion solvent mixing a polymer compound, a drug and a water-insoluble organic solvent to prepare a dispersed phase mixing the dispersed phase with the dispersion solvent mixed with the water-insoluble organic solvent to prepare an emulsion and adding a base or an acid to the prepared emulsion. With the method, it is possible to prepare a drug-containing polymeric microsphere cost-effectively and conveniently.
