1. A single or multi-route map matching apparatus in a system which provides a navigation service via a mobile communication terminal, the map matching apparatus comprising: an information center for calculating an optimum route to a destination inputted by a user based upon a present location of the mobile communication terminal, and generating a format of route data based upon the calculated optimum route; and an Intelligent Transportation System (ITS) terminal for detecting the present location of the mobile terminal to generate location data, processing the route data, performing map matching based upon the location data to determine whether the user travels on a given route or departs from the route, and performing road guidance based upon a result of the map matching.