VEHICLE DOOR DEVICE

A vehicle door device includes a first link arm and a second link arm each having a first pivot coupling point with respect to a vehicle body and a second pivot coupling point with respect to a door of a vehicle, and a biasing force applying device configured to, during opening and closing operation of the door based on an operation of a link mechanism formed by the first link arm and the second link arm, apply, to the door, a biasing force in a direction in which a rotational moment around the second pivot coupling point generated based on inertia of the door generated in the door accompanied by the operation of the link mechanism is reduced.