To provide a navigation device to be mounted on a car which enables a driver to easily recognize whether the driver's car can enter roads crossing the road on which he drives the car.

A detection circuit 14-1 detects one-way roads prohibiting the entry from the road on which a driver drives a car out of the information of the roads displayed on a display unit 10 and a discriminating circuit 14-2 judges whether the detected roads are one-way for the whole day or one-way depending on a time period. The discriminating circuit 14-3 judges that it is the time for the one-way roads judged one-way depending on a time period for one-way, the first indication prefixed under the control of a display control circuit 14-4 is displayed to each roads judged one-way for the whole day and the second indication is displayed under the control of the display control circuit 14-4 to each side of the one-way roads depending on a time period which is not at towed to enter within the time when the roads are not allowed to enter.