A navigation system for providing location information of another party's moving object, comprising: (a) a GPS receiver configured to receive location data from a plurality of GPS satellites; (b) a storage unit configured to store map data; (c) a display unit configured to display, on a screen, the stored map data and location information of said another party's moving object on the map data; (d) a voice processing unit configured to process voice signal and to output the processed voice signal; (e) an input unit configured to receive from a user a variety of key signals including an input for a location information request message requesting location information of said another party's moving object, wherein the location information request message comprises identification information of said another party's moving object, which includes a telephone number of a second navigation system of said another party's moving object, a subscriber information of the navigation system and current location information of the navigation system; (f) a wireless communication unit configured to transmit the location information request message to a traffic information center (250; 430) and receive a location information reception message from the traffic center(250; 430); and (g) a control unit configured to control each of the units, control the location information request message to be transmitted to the wireless communication unit, control the received location information of said another party's moving object in the location information reception message to be displayed on the screen, and control the display unit to display the received location information of said another party's moving object; the control unit further configured to request the shortest traveling route between the current location of the navigation system and the received location information of said another party's moving object displayed on the screen and to display on the screen the shortest traveling route the control unit is further configured to, if the user selects the location information of another party's moving object displayed on the screen, automatically connect to the telephone number of said second navigation system by the wireless communication unit. (a) a GPS receiver configured to receive location data from a plurality of GPS satellites; (b) a storage unit configured to store map data; (c) a display unit configured to display, on a screen, the stored map data and location information of said another party's moving object on the map data; (d) a voice processing unit configured to process voice signal and to output the processed voice signal; (e) an input unit configured to receive from a user a variety of key signals including an input for a location information request message requesting location information of said another party's moving object, wherein the location information request message comprises identification information of said another party's moving object, which includes a telephone number of a second navigation system of said another party's moving object, a subscriber information of the navigation system and current location information of the navigation system; (f) a wireless communication unit configured to transmit the location information request message to a traffic information center (250; 430) and receive a location information reception message from the traffic center(250; 430); and (g) a control unit configured to control each of the units, control the location information request message to be transmitted to the wireless communication unit, control the received location information of said another party's moving object in the location information reception message to be displayed on the screen, and control the display unit to display the received location information of said another party's moving object; the control unit further configured to request the shortest traveling route between the current location of the navigation system and the received location information of said another party's moving object displayed on the screen and to display on the screen the shortest traveling route