A cell reselection function in a mobile station (MS) through an adjacent cell search is provided. The MS in an idle state obtains its own moving speed and current location using Global Positioning System (GPS) location information, calculates a predicted moving location, and stores the predicted moving location. Thereafter, when measurement values of adjacent cells are similar, or when the adjacent cells are located in different location areas (LAs), the MS can efficiently search for the best cell from among the adjacent cells based on the location information and select the best cell as a new serving cell.