In a vehicular air conditioning apparatus, a first blower unit is connected by a connection duct to a side portion of a casing having respective air passages defined therein. In addition, air that is supplied to the interior of the casing from the first blower unit, and which is heated by the heater core, is blown from the fifth front passage alongside the heater core directly into the sixth front passage via sub-defroster dampers, and is blown out toward the front seat of the vehicle from a defroster blow-out port, which is disposed in the sixth front passage.