An apparatus and method for displaying a detailed map of a selected area of a displayed map received through a network are provided. If a detailed map of a particular area is requested by a user, data on the detailed map for the particular area is provided by a map provider server through a network and combined with data on the original map. A map including maps drawn to two different scales is displayed on a display device, i.e., the original map is continuously displayed while only the particular area is replaced by the detailed map. Therefore, the readability of the map is improved, and desired geographical information can be easily obtained.