PURPOSE: To provide an air conditioning device which fascilitates a light weight of a vehicle, a low weight and a low cost of the system, and can carry out the air conditioning in a good ventilation rate without generating an air flow feeling or an uneven air flowing, and furthermore, can secure the air conditioning of each passenger room.

CONSTITUTION: Blowout ports 5 to blow out air-conditioning air to a room 11 are provided around the lower side 11 of a vehicle A, and exhaust ports 6 to exhaust the air in the room 11 to the outside are provided around the upper side 9 of the room 11, respectively. And the air-conditioning air blown out into the room 11 is raised from the lower side to the upper side of the room 11, and then exhausted.