The present invention provides a wet etching apparatus. The wet etching apparatus comprises: an etching chamber, comprising an etching chamber inlet at a front end and an etching chamber outlet at a rear end, wherein in the etching chamber, a film to be etched on a substrate is subject to etching with an etching liquid; and a decrystallization device, which washes residual etching liquid or etching liquid crystal formed by the etching liquid at the etching chamber inlet and/or etching chamber outlet with a washing liquid. By means of the decrystallization device, residual etching liquid or etching liquid crystal formed by the etching liquid at the etching chamber inlet and the etching chamber outlet can be effectively removed, thus improving operation ratio and cleanness of the apparatus as well as quality of products.