In a vehicle air conditioner, a first air passage through which outside air flows and a second air passage through which inside air flows are provided to be partitioned from each other, so that outside air in the first air passage is blown toward a front seat side of a passenger compartment from a front air outlet after passing through a first part of a heat exchanger, and inside air in the second air passage is blown toward a rear seat side of the passenger compartment from a rear air outlet after passing through a second part of the heat exchanger, during a double layer flow mode. Thus, in the second air passage, temperature of air sucked from an inside air port can be set to temperature of inside air inside the passenger compartment, while air pressure loss due to an inside air suction is decreased. As a result, in the vehicle air conditioner, air-conditioning capacity for the rear seat side is improved.