A rear face inlet 25 and a foot inlet 28, and a rear face duct portion 26 and a foot duct portion 31 which are adapted to distribute air from the inlets, respectively, are disposed in alignment with each other in a transverse direction of a vehicle. As a result, a conventional overlapping portion where the rear face inlet and the foot inlet are made to overlap each other vertically somewhere along the length of each of the inlets in a transverse direction of the vehicle and a conventional overlapping portion where the rear face duct and the rear foot duct are disposed in such a manner as to overlap each other in a longitudinal direction of the vehicle somewhere along the length of a downwardly extending portion of each of the ducts can be eliminated, whereby the air conditioning unit can be constructed so as to be decreased in size vertically and longitudinally.