To provide a droplet forming technology capable of stably sorting a droplet.
Provided is a microparticle sorting device provided with a voltage supply unit that supplies a drive voltage to a vibration element that applies a vibration to an orifice that generates a fluid stream, a control unit that controls a driving condition supplied to the vibration element on the basis of a relative relationship between a droplet discharged from the orifice and a satellite droplet present between droplets, and a sorting unit that sorts the droplet containing microparticles on the basis of optical information detected from the microparticles flowing through a flow path.