The present invention provides a method for preparing polylactic acid-based resin particles, polylactic acid-based resin particles which have porous shape and high oil absorbent amount in small particle diameter useful as cosmetics, polylactic acid-based resin particles which have smooth surface and narrow distribution of particle diameter in spherical form useful as toner, and cosmetics using those polylactic acid-based resin particles. The method for preparing polylactic acid-based resin comprises dissolving a polylactic acid-based resin (A) and a polymer (B) different from the polylactic acid-based resin in a ether-based organic solvent (C) and applying shear stress thereon to form emulsion, then contacting with a poor solvent of polylactic acid-based resin (A). According to the preparing method, the porous polylactic acid-based resin particles that have enthalpy of fusion of 5J/g and more, small particle diameter, and high oil absorbent amount are provided, or the polylactic acid-based resin particles that have enthalpy of fusion of less 5J/g, narrow distribution of particle diameter in spherical form, and smooth surface are provided.
