An apparatus and method for reducing the power consumed by mobile communication terminal having a wireless LAN connection function. When a data communication operation is started, a control unit determines whether a connection to a wireless LAN is available, and if so, detects the battery remaining amount in a battery unit. If the battery remaining amount is equal to or greater than a first threshold, data communication is performed through the wireless LAN connection. When the battery remaining amount is smaller than the first threshold, a screen for recommending connection through cellular communication is displayed on a display unit. When the battery remaining amount becomes smaller than a second threshold, which is smaller than the first threshold, a power source control unit performs a predetermined power saving operation.