The invention addresses the problem of providing a method for producing microparticles. Provided is a method for producing microparticles. For the first process, seed microparticles are separated in a thin film fluid that forms between at least two processing surfaces, which are disposed facing each other, which can approach or separate from each other and at least one of which rotates relative to the other, and the fluid comprising the separated seed microparticles is discharged as a discharge fluid. Subsequently, for the second process, the separated seed microparticles are grown in the discharged discharge fluid to obtain the intended microparticles. Uniform and homogeneous microparticles are obtained as a result of the microparticle producing method comprising the two process.