To provide a device that has superior enforcement property and reliability and performs the ventilation and air conditioning of an entire house corresponding to an indoor environment, and its controlling method.

In a ventilation air-conditioning device, a control device for controlling a device body self-supportingly and a transmitting/receiving device by a radio electronic wave 11 are built in a device body 1 consisting of a heat exchanging unit 3 for heat-exchanging air inside and outside a house by suction air and exhaust, an air-conditioning unit 4 for cooling and heating the heat- exchanged indoor and outdoor air, and a blast unit for distributing and supplying the cooled or heated indoor air to a plurality of rooms in the house. The operation of the ventilation air-conditioning device can be controlled based on a determined amount of control in a control panel 10 being connected to the device body 1 by the radio electronic wave, thus simplifying the enforcement and the wiring of the ventilation air-conditioning device and maintaining the minimum functions of the ventilation air-conditioning device in case of the failure in the radio electronic wave 11.