An air conditioner for a vehicle includes: a compressor (21); an internal heat exchanger (22, 24) which exchanges heat between the refrigerant and air in an interior space; an external heat exchanger (23) which exchanges heat between the refrigerant and outside air; a battery (5); a battery heat exchanger (29) which exchanges heat between the refrigerant and the battery by causing the refrigerant, which travels to the compressor from the external heat exchanger, to go through the battery heat exchanger; a throttle adjusting part (30) which is arranged in a refrigerant flow passage on an upstream side of the battery heat exchanger; and a control unit (40). The control unit (40) controls the flow of the refrigerant through the throttle adjusting part based on an extra heat exchange capacity that is an extra capacity of the external heat exchanger with respect to the internal heat exchanger.