To provide a medium washing apparatus which can increase the re-usability of two or more kinds of washing solutions in the case where a medium is washed by separately using these washing solutions.

The medium washing apparatus is for washing a medium by separately using two or more kinds of washing solutions while transporting the medium in the transverse direction and has a plurality of washing mechanisms each for washing the medium by using one kind washing solution and arranged along the medium in the transportation direction. Each washing mechanism has a first tank for storing a washing solution, at least one washing means to which the washing solution in the first tank is supplied to wash the medium while being brought into contact with the medium, a purifying means for purifying the washing solution used for washing the medium, a second tank for storing the washing solution used for washing the medium, and a washing solution supply means for supplying the washing solution in the second tank to the first tank.