A vehicle air-conditioning unit includes a plurality of doors for opening and closing an air passage within a unit case, and a link mechanism. The link mechanism has levers fixed to rotary shafts of the doors, respectively, to rotate with the rotary shafts of the doors, a base fixed to the unit case, and a main link rotatably or slidably supported on the base, being engaged with the levers for rotating the levers when driven by a driving means. The levers and the main link are disposed between the base and the unit case.