To provide a collective vestibule machine mountable with multiple kinds of key switches different in mounting structure.

In the collective vestibule machine 100 mounted with the key switch, a back face 1a of a collective vestibule machine cover 1 is provided with a mounting adapter 7 of U-shaped cross section mounted in a reversely mountable and detachable manner, and the right and left sides of an opening part for the key switch of the collective vestibule machine cover 1 are provided with fixing pieces 8 for the mounting adapter 7 erectly from the back face 1a of the collective vestibule machine cover 1.