To provide a washing machine which can be easily handled and in which occurrence of troubles due to fine particles of acrylic resin in use as washing material can be restrained.

A rotation member 1 in which a large number of through holes 2, through which pachinko balls can be passed, are formed is disposed with its axis being oriented horizontally or approximately horizontally and rotated and balls 8 are supplied from one of the ends of the axis. The balls 8 are cleaned while the surfaces thereof being polished, while they are passed through the holes 2.