In a dissolving step, a poorly soluble drug and a dispersion stabilizer are dissolved in a volatile organic solvent. In a fixing step, the organic solvent, contained in a solution obtained in the dissolving step, is removed by evaporation, pellet-form residues 1 are obtained by the organic solvent removal, and the residues 1 are fixed on respective bottom surfaces of a plurality of locations of a container 30. In a water injecting step, water 2 is injected into each of a plurality of recesses 31 of the container 30. In an irradiating step, laser light L, emitted from a light irradiating unit 20, is irradiated simultaneously or successively on the residues 1 fixed on the respective bottom surfaces of the recesses 31 of the container 30, and the residues 1 are thereby pulverized and made into microparticles and a microparticle dispersion liquid, constituted of the microparticles being dispersed in the water 2, is manufactured.