The problem addressed by the present invention is to provide a method for producing microparticles. Provided is a method that is for producing microparticles and that is characterized by containing at least the the following two steps: (I) a step for preparing a microparticle starting material solution by dissolving at least one type of microparticle starting material in a solvent using high speed stirring or ultrasonic waves, and (II) a step for precipitating microparticles by mixing the microparticle starting material solution and at least one type of precipitation solvent for precipitating the microparticle starting material in a thin film fluid formed between at least two processing surfaces that are disposed facing each other, are able to approach/separate from each other, and of which at least one rotates relative to the others.