A vehicle air conditioning device, comprising: an outside air ventilation flue (8,9) through which outside air that is sucked in from outside a cabin of a vehicle flows; an inside air ventilation flue through which inside air that is sucked in from inside the cabin of the vehicle flows; an evaporator that is disposed on a downstream side of the outside air ventilation flue (8,9) and the outside air ventilation flue; an outlet-side ventilation flue through which air that flows out from the evaporator flows; a heater that is disposed on a downstream side of the evaporator; a heater-side ventilation flue that causes air that flows out from the evaporator to flow via the heater to the outlet-side ventilation flue; and a damper that is formed so as to span the evaporator in a width direction on the downstream side of the evaporator, and that, by rotating around a shaft extending in the width direction of the evaporator, opens/closes a flow path of air that flows directly to the outlet-side ventilation flue from the evaporator and a flow path of air that flows from the evaporator via the heater-side ventilation flue to the outlet-side ventilation flue, respectively; wherein: the outside air ventilation flue (8,9) is formed so that the outside air flows to a predetermined position in the width direction of the evaporator; the inside air ventilation flue is formed so that the inside air flows to another predetermined position in the width direction of the evaporator; and characterised in that: the outside air ventilation flue (8,9) is formed so that outside air flows to one end side and the other end side in the width direction of the evaporator; and the inside air ventilation flue is formed so that inside air flows to a central site in the width direction of the evaporator. an outside air ventilation flue (8,9) through which outside air that is sucked in from outside a cabin of a vehicle flows; an inside air ventilation flue through which inside air that is sucked in from inside the cabin of the vehicle flows; an evaporator that is disposed on a downstream side of the outside air ventilation flue (8,9) and the outside air ventilation flue; an outlet-side ventilation flue through which air that flows out from the evaporator flows; a heater that is disposed on a downstream side of the evaporator; a heater-side ventilation flue that causes air that flows out from the evaporator to flow via the heater to the outlet-side ventilation flue; and a damper that is formed so as to span the evaporator in a width direction on the downstream side of the evaporator, and that, by rotating around a shaft extending in the width direction of the evaporator, opens/closes a flow path of air that flows directly to the outlet-side ventilation flue from the evaporator and a flow path of air that flows from the evaporator via the heater-side ventilation flue to the outlet-side ventilation flue, respectively; wherein: the outside air ventilation flue (8,9) is formed so that the outside air flows to a predetermined position in the width direction of the evaporator; the inside air ventilation flue is formed so that the inside air flows to another predetermined position in the width direction of the evaporator; and characterised in that: the outside air ventilation flue (8,9) is formed so that outside air flows to one end side and the other end side in the width direction of the evaporator; and the inside air ventilation flue is formed so that inside air flows to a central site in the width direction of the evaporator. the outside air ventilation flue (8,9) is formed so that the outside air flows to a predetermined position in the width direction of the evaporator; the inside air ventilation flue is formed so that the inside air flows to another predetermined position in the width direction of the evaporator; and characterised in that: the outside air ventilation flue (8,9) is formed so that outside air flows to one end side and the other end side in the width direction of the evaporator; and the inside air ventilation flue is formed so that inside air flows to a central site in the width direction of the evaporator. the outside air ventilation flue (8,9) is formed so that outside air flows to one end side and the other end side in the width direction of the evaporator; and the inside air ventilation flue is formed so that inside air flows to a central site in the width direction of the evaporator.