Vehicle air-conditioning apparatus

To provide a vehicle air-conditioning apparatus provided with a sliding-type door mechanism configured to prevent increases in air ventilation resistance and noise in a fully-cooling mode or a fully-hot mode further reliably. A vehicle air-conditioning apparatus provided with a sliding-type door mechanism according to invention includes: a plate-shaped sliding-type door (3) arranged so as to be slidable across a plurality of air channels and configured to adjust the plurality of air channels to be opened and closed; a driven gear (9) provided on the sliding-type door so as to extend along a direction of movement of the sliding-type door, a plurality of rotational drive units (7) including a rotational drive gear (5) configured to drive the sliding-type door by engaging the driven gear (9); and a coupling shaft (8) configured to couple the plurality of rotational drive units (7) at a position deviated from centers of rotation (26).