To surely prevent a rotator or a washing web from being damaged by bringing the sections being wetted with a washing liquid of the washing web into contact with the rotator regardless of the quality of the material of washing materials or the structure of a washing device.

A washing nozzle 6g is provided on the upstream side in the moving direction of a washing cloth 6i and a lower side from a contact section at which the washing cloth 6i and a rubber drum 5 come into contact. As an initial cloth feeding, the washing cloth 6i is idly fed twice during a period from when the washing liquid is fed to the washing cloth 6i to when the washing cloth 6i is brought into contact with the rubber drum 5, and the section of the washing cloth 6i to which the washing liquid has been fed is made into the contact section with the rubber drum 5. The frequency of the initial cloth feeding is not limited to twice, and may be once, or may be three times or more.