The present provides a method for preparing resin fine particles of a
homogeneous particle size used in the fields of chemistry, medicine,
electronic material or the like, resin fine particles, and a production
apparatus for resin fine particles.The present invention provides a
method for preparing a resin fine particle, which comprises discharging a
liquid comprising a polymerizable monomer as a dispersion phase into a
continuous phase; splitting the liquid comprising the polymerizable
monomer by applying mechanical vibration to form a liquid droplet; and
polymerizing the liquid droplet in a state without splitting or
integrating the liquid droplet, said method comprising recognizing a
state of said liquid being split into a liquid droplet, and a condition
of said discharging and/or said mechanical vibration of the liquid being
determined by feedback from a result of the recognition.