PURPOSE: To easily and surely treat thrown crude refuse and to form the pressure crushed and dehydrated crude refuse optimum for a crude refuse retreating machine.

CONSTITUTION: This apparatus for formation of the pressure crushed and dehydrated crude refuse is provided with a cylindrical casing 1 having a chute 2 for accepting the charged crude refuse and a dehydrating port 3 and a discharge port 4 for discharging the treated crude refuse on the rear surface, a movable bottom plate 10 disposed above the discharge port of this causing 1 and a moving device 9 adapted for moving this bottom plate. Further, the apparatus is formed of a piston 6 which vertically moves within the casing, a square-meshed cutting blades 7 which are disposed under this piston and an extrusion piston 8 which is disposed freely retractably between the cutting blades and has many piston pieces for extruding the pressure crushed and dehydrated crude refuse.