To facilitate the arrangement of apparatuses for the supply and discharge of a treating liquid, piping, and others, as well as maintenance and the installation of piping of an exhaust system and to improve exhaust efficiency.

By installing a side part exhaust passage 24 formed from a treatment tank 21 for storing a treating liquid in which semiconductor wafers W are immersed, a cylindrical container 22a having a treatment chamber 23 for housing the treatment tank 21, the side wall 26 of the container 22a, and the first partition wall 28 having an erect wall 27 standing from the bottom part 23a of the treatment chamber 23 and a bottom part exhaust passage 25 which is formed from the bottom plate 30 of the container 22a and the second partition wall 29 which is bent nearly horizontally from the lower end part of the first partition wall 28 and communicates with the side part exhaust passage 24, the arrangement of apparatuses for the supply and discharge of semiconductor wafers W, piping, and others is facilitated, maintenance and the installation of piping of an exhaust system are also facilitated, and exhaust efficiency can be improved.