This vehicle device operation apparatus is provided with: a deforming body which is configured so as to be attached to a vehicle seat and in which a fluid is sealed; and a control device. The control device is configured so as to detect the inner pressure of the deforming body, detect an adjusting operation which is an occupant's operation for adjusting the operated state of a vehicle device on the basis of a change in inner pressure of the deforming body caused by pressing of the deforming body through the body movement of an occupant seated on the seat, and execute adjustment control for adjusting the operated state of the vehicle device in response to the detection of the adjusting operation.