PURPOSE: To reduce the crushing of sand grains and to regenerate casting sand at high efficiency and high yield by putting the sand to be regenerated in a processing container and vibrating the container to make the sand collide against inside of the container.

CONSTITUTION: Sand A to be regenerated is put into the main body 1a of a processing container provided with plural dust discharge ports 5 and an upper cover 1b is fixed. When the processing container 1 is vibrated vertically by rotating a crank wheel 7 at high speed, the sand A to be regenerated collides repeatedly against upper and lower impact boards 3, 4, binder, carbon etc. adhered on the surface of sand grains peel off gradually. Separated dust B is discharged to the outside from the dust discharge ports 5 in the course of regenerating process. By this method, number of times of impact to which regenerated sand A is subjected is nearly twice the number of times of vibration of the container 1, and binder, carbon etc. are removed effectively. Regenerated sand obtained by this method can be used again directly without rinsing, etc.