PURPOSE: To provide a navigation device provided with an additional function storiang variou kinds of data in relation to map data and displaying it.

CONSTITUTION: A memory registering optional data is provided in the navigation device. In the memory, a registered date, a name, a telephone number and memo data are stored. Thus, data retrieval is executable by the registered date, the name and the telephone number, etc. When retrieval data is displayed on a display device 12 are telephone number data 23 having an area code is contained and the touch switch 13d of a (map) is depressed, the map of the area of the area code (06) of the telephone number data 23 is displayed on the display device 12. Then, the registered data and the map are called by relating to the registered data and the map by the area code of the telephone number and the registered data is controlled relating to the map.