A wet cleaning apparatus can remove trace heavy metals, colloidal matter or other impurities contained in ultra-pure water to be used as rinse water in semiconductor cleaning processes and suppress deposit of trace impurities such as heavy metals or other particles that would otherwise cause characteristics of such devices to deteriorate. A wet cleaning apparatus for rinsing with ultra-pure water as a rinse liquid by supplying ultra-pure water through a piping to a rinse location inside the apparatus. The rinse location is a point of use of the ultra-pure water. The wet cleaning apparatus includes a module filled with porous film in which polymer chains having at least one of an anion exchange group, a cation exchange group, and a chelating group are held in the middle of the piping positioned inside the apparatus. The wet cleaning apparatus further includes a means for adding hydrogen gas to the rinse liquid.