Air conditioning system for vehicles

An air conditioning system for vehicles (1) having an air conditioning unit (2) which has an air path (4), an evaporator (5), a heater core (6) and an air mixing damper (7) characterized in that the air conditioning unit (2) is disposed so as to be inclined relative to a horizontal plane of a vehicle, and the evaporator (5) is disposed to be inclined relative to the extending direction of the air path (4) so that the extending direction of the evaporator (5) approaches a vertical direction. The system may be made small and thin, the length of air path in the system may be decreased, the air conditioning performance may be increased, and the cost for manufacture and installation may be reduced.