The invention provides a discharging device of expanded perlite. The discharging device comprises a telescopic cylinder and a hopper, the telescopic cylinder is welded to the side end of the hopper, the telescopic cylinder is fixed at the lower end of a cover plate, a rotating disc is arranged at the upper end of the cover plate, a rotating shaft is fixed in the middle of the lower end of the rotating disc, the rotating shaft is arranged at the lower end of the cover plate through a bearing and penetrates through the cover plate and is connected with the rotating disc, the rotating shaft is fixed in the middle of the upper end of a sealing plug, and spiral blades are fixed at the lower end of the sealing plug. According to the discharging device, the raw materials in the hopper can be stirred, the blockage phenomenon in the hopper can be effectively prevented, the hopper is sealed through the cover plate and the sealing plug, the dustproof function is effectively achieved, and residualmaterials in the hopper can be effectively prevented from being discharged into the expansion equipment, the device is convenient to use, the use effect is improved, and the functionality is increased.