To legibly display the relation between the current position of a vehicle and the whole area of object to be charged when the area of object to be charged closes in, and to enable a route for avoiding entering the charge area to be easily judged.

The device is provided with a storing means 6 which stores data relative to road map data and the area of object to be charged, a current position detecting means 1 which detects the current position of the vehicle, a displaying means 3 which displays a road map, an approach judging means 9 which judges whether the vehicle approaches to the area of object to be charged based on the data of the current position of the vehicle and the data of the area of object to be charged, a scale changing means 9 which changes the scale of the road map displayed on the displaying means 3 into such a scale that the current position of the vehicle and the whole area of object to be charged to which the vehicle approaches are contained in a display screen. The displaying means 3 displays the current position of the vehicle and the area of object to be charged to which the vehicle approaches on the road map with the scale changed in accordance with the approach of the vehicle to the area of object to be charged.