To provide an economical cleaning means having superior cleaning effect for surely cleaning a long endoscope in a small cleaning space with a small amount of the cleaning liquid.

A cleaning tube 12 capable of inserting the endoscope for cleaning the same, is made of a flexible looped tube, a by-pass passage 50 is connected between a first end 12a side and a second end 12b side of the cleaning tube 12, the cleaning liquid in the cleaning tube 12 is forcibly circulated from the first end 12a side to the second end 12b side by the by-pass passage 50 to produce the circulated current of the cleaning liquid flowing inside of the cleaning tube 12 from the second end 12b side to the first end 12a side, and the endoscope is cleaned by the circulated current.