The present invention provides a fluidized bed device for handling fine particles as a fluidized bed in a medicine manufacturing process, a cosmetic manufacturing process, a food manufacturing process, a chemical manufacturing process and the like, wherein influence of static electricity is suppressed, and a method for neutralizing the static electricity using that device. The fluidized bed device includes an X-ray irradiation unit for irradiating fine particles in the fluidized bed device with X-rays.