A method for auto updating application program suitable for a global position system (GPS) navigator is provided. The method comprises the following steps. First, a map-update short message is sent to the GPS navigator at a client terminal from a wireless station. Then, a map-downloading program inside the GPS navigator is woken up when the GPS navigator receives the map-update short message. Then, connecting to a map server through the map-update short message when a user decides to update the map. Accordingly, a newest electronic map can be downloaded from the wireless station.