To provide a device for crushing, sizing and grinding by which surplus soil in a processing chamber can be simply discharged in a short time without any manual work in order to perform maintenance work.

The device is provided with a surplus soil discharging port 16 connectedly protruded downwards from a bottom surface 11 of the processing chamber 4, a surplus soil discharging conveyor 17 covering the surplus soil discharging port 16 from a lower side and a guiding part 18 for guiding the surplus soil carried out from the surplus soil discharging port 16 by the surplus soil discharging conveyor 17. When operating, the surplus soil discharging port 16 is filled with material to be processed so that the material to be processed overflows to the guiding part 18. Before maintenance work, the surplus soil discharging conveyor 17 is operated and the material to be processed in the processing chamber 4 is successively carried out from the surplus soil discharging port 16 by the surplus soil discharging conveyor.