A nonvolatile memory is accessed by a memory control circuit and stores temperature information indicating a temperature measured by a temperature sensor. A power supply control circuit supplies a first power supply voltage to the temperature sensor in response to a request for temperature measurement received via an antenna, and supplies a second power supply voltage to the nonvolatile memory and the memory control circuit after the temperature sensor measures the temperature. While the temperature sensor is measuring the temperature, the nonvolatile memory and the memory control circuit do not operate and thus do not generate heat. Therefore, the temperature sensor can accurately measure the temperature without being influenced from the heat generation caused by the operation of circuits in an RFID transponder.