To miniaturize a device, and reduce the weight thereof, and improve the function thereof by forming one surface of a heat exchanger with an air flow-in part and an air flow-out part, and forming the other surface of the heat exchanger with a wind direction reversing space, and arranging a blower and a heater core in the surface formed with the air flow-in part and the air flow-out part, and furthermore, providing an intermediate partitioning plate for dividing the downstream in the cross direction.

One surface 4a of an evaporator 4 is formed with an air flow-in part and an air flow-out part, and a blower 5 is arranged opposite to a part of the surface 4a, and a heat core 3 is arranged with inclination so as to correspond to a part of the residual part. A unit duct 2 is provided with an inside and outside switching damper 9 and air intake ports 10a, 10b. The other surface 4b of the evaporator 4 is formed with a wind direction reversing space 6 for reversing the air, which passed through the evaporator 4. An intermediate partitioning plate 16 for dividing the downstream of the evaporator 4 in the cross direction thereof is provided so as to divide the downstream to ventilation passages 15a, 15b. With this structure, air flow is evened so as to improve the air conditioning performance, and miniaturization of device and reduction of weight thereof are realized.