To achieve downsizing of a rotary damper which has a plate-like part for guiding air in an air mix space without worsening air mix property and reducing blowout air quantity and make an air conditioner for vehicle compact.

On a heat damper 13, a plate-like part 13f which extends toward a cool air introduction side of an air mix space R3 from vicinity of a downstream end of a warm air passage R2, and guides warm air flowed into the air mix space R3 from the warm air passage R2 toward the cool air introduction side of the air mix space R3 is provided. The plate-like part 13f is disposed between rotation shafts 13a, 13b of the heat damper 13 and a closed wall part 13e.