PURPOSE: To select a route which is the easiest to pass so as to advance by calculating the optimum degrees of respective routes from the received degrees of traffic jam at respective intersection and extracting the route of the high optimum degree.

CONSTITUTION: A navigation device 1 is provided with a traffic information receiver 11, a map information input device 12, a target place input device 13, a present place input device 14, a route generation device 15, an optimum degree arithmetic unit 16 and an optimum route display device 17. The navigation device 1 receives traffic information from a traffic information transmitter 2. In this case, the target place input device 13 inputs a target place by pointing it on a display. The optimum degree arithmetic unit 16 calculates the optimum degree of the route reaching the target place from inputted traffic information, map information, the target place and the present place. The optimum route display device 17 displays the route of the highest optimum degree on the display.