The present invention is to provide a cellular phone capable of measuring temperature including a liquid crystal display, a CPU and an IR temperature measurement means coupled to the CPU, wherein a first GPO pin and a second GPO pin of the CPU are adapted to control power supply of a power supply IC and start or stop of the IR temperature measurement means respectively, and in response to receiving a temperature measurement signal, the CPU performs a plurality of processing and conversion steps to show a corresponding temperature on the display.