PURPOSE: To dip a material to be cleaned in a cleaning solution to enhance the cleaning efficiency in a rotary drum type cleaning device for cleaning the material to be cleaned by injecting the cleaning solution to the material to be cleaned in a rotary drum.

CONSTITUTION: In a dip cleaning part D of a cleaning process A, a non- perforated outer peripheral shield plate 71 is fixed on the outer peripheral surface of the drum main body 11 countlessly perforated on the cylindrical surface. In the bottom part of the drum main body 11, a cleaning solution reservoir 70 is formed to dip the material to be cleaned into the cleaning solution since a part of the cleaning solution from an upper cleaning solution feed pipe 31 is shielded by the outer peripheral shield plate 71.