An air conditioner for a vehicle includes: an air-conditioning case having therein an air flow passage through which air toward the vehicle interior flows, and an outlet opening formed at an upper part of the air-conditioning case and through which the air toward the vehicle interior passes； a heat exchanger disposed on a lower side of the outlet opening inside the air-conditioning case to exchange heat between air toward the vehicle interior and a heat-exchange medium； and an ion generator that includes electrodes to generate ions. The ion generator is mounted on the air-conditioning case such that the electrodes are exposed in air flowing through the air flow passage. The air-conditioning case has a collision-side wall surface with which the airflow having passed through the heat exchanger collides to be directed upward, and a lateral-side wall surface connected to and laterally adjacent to the collision-side wall surface. The ion generator is disposed at a predetermined position of the collision-side wall surface or the lateral-side wall surface.
