An endoscope reprocessor includes: a holding member to/from which a filtering tool is attachable and detachable; a fluid introduction conduit and a fluid discharge conduit that communicate with the filtering tool in a state in which the filtering tool is attached to the holding member; a moving member configured to, when the filtering tool is attached to the holding member and a weight of the filtering tool is less than a predetermined value, position the filtering tool in a first position and, when the filtering tool is attached to the holding member and the weight of the filtering tool is greater than or equal to the predetermined value, position the filtering tool in a second position that is different from the first position; and a hindering unit configured to, when the filtering tool is positioned in the second position, hinder removal of the filtering tool from the holding member.