The invention provides self-cured microspheres, which are prepared from a temperature-sensitive material with a lower critical soluble temperature, wherein the average particle size of the self-cured microspheres is in the range of 50nm to 100 microns, and the particle size distribution coefficient of the self-cured microspheres is smaller than 20%. The self-cured microspheres are prepared by thefollowing steps of: 1) providing a solution of the temperature-sensitive material added with bioactive substances or functional components as a dispersed phase; 2) providing emulsifying agent dissolved solvents which are dispersed and are insoluble with each other as continuous phases; 3) dispersing the dispersed phase in step 1) into the continuous phases in step 2) to obtain a pre-emulsion; 4) enabling the pre-emulsion in step 3) to pass through a microporous membrane for one time or a plurality of times under a pressure to obtain an emulsion; 5) heating the emulsion in step 4) to above thelower critical soluble temperature of the adopted temperature-sensitive material, so that liquid drops are cured to obtain the microspheres. The self-cured microspheres is suitable for serving as carriers of bioactive substances.