Abstract: A wireless temperature sensor that is attached to the patient's skin in order to measure the patient's temperature, thereby adopting a patient moving in the facilities as a measuring object. The wireless sensor is a wireless temperature sensor?having a function of wirelessly transmitting measured data through a chip antenna, and the chip antenna has a length of a shortening coefficient so as to be received in a container, and is received in the container. In addition, the invention provides a wireless interface device in which a wireless communication function is provided to a wireless communication card having a low carrier frequency, a small antenna, an enlarged communication distance, and low power consumption. Furthermore, the invention provides a wireless sensor system in which the sensor notifies a patient of surrounding environment information by a wireless communication device whereby a base station collects the environment information from a plurality of sensors.