To provide an apparatus for crushing expanded polystyrene, in which spent expanded polystyrene is crushed so rationally that it is easily reused.

A crusher C having a plurality of disk-shaped toothed cutters 3 fixed aslant to a columnar rotating body 1 having a shaft 2 in the center in parallel at the predetermined intervals is placed in a crushing chamber B arranged separately in the main body A of this apparatus via a bearing 5 so that one end of the shaft 2 is projected to the outside of the crushing chamber B. The crusher is rotated by a motor 6 arranged separately in the main body A via a belt 6 stretched between a pulley 4 fitted to the projected shaft 2 and another pulley 8 of the motor 6.