To obtain a navigation system capable of appropriately displaying information on other vehicles.

In the case that the present location of another vehicle acquired by a communication module 14 is not included within the range of objects to be displayed specified by a present display scale, etc., stored in a storage part 18, a processing control part 16 displays a symbol to indicate the present location of one's own vehicle and a symbol to indicate that the present location of other vehicle lies outside the range of objects to be displayed on a display part 19 without changing the display scale. After this, when instructions for displaying one's own vehicle and other vehicles are inputted from an operating part 15, the display scale is changed into a scale capable of displaying both vehicles to display the present locations of one's own vehicle and the another vehicle. Then after a predetermined time is elapsed, the processing control part 16 returns to the original display scale and displays the symbol to indicate the present location of one's own vehicle and the symbol to indicate that the present location of the another vehicle lies outside the range of objects to be displayed on a display part 19 again.