To enable the easy mounting and piping of a hood to be located under a housing means with a duct arranged on the back part in a short time.

This device comprises a support means 15 mounted on a wall 1 or a ceiling 12 and having a laterally protruding part 16 protruded forward from a wall surface 1a; a ventilation means 6 having the hood 5 mounted on at least the lower part of the lateral protruding part 16 among the lower part of the lateral protruding part 16 of the support means 15, the wall 1 and the ceiling 12 and the duct 11 extended outdoors from the hood 5, and the housing means 4 mounted on at least the front part of the lateral protruding part 16 of the front part of the lateral protruding part 16 and the ceiling 12.