A temperature measuring system includes, e.g., a temperature measuring pad configured to measure a temperature of an object on which the temperature measuring pad is to be disposed, and a reader configured to read temperature information including the measured temperature and an ID code given to the temperature measuring pad. The temperature measuring pad includes, e.g., an antenna portion for receiving a radio wave emitted from the reader, an electric power generating portion for generating electric power from the radio wave received by the antenna portion, a temperature sensor for measuring the temperature of the object and an output portion for wirelessly outputting the temperature information, the output portion being operated by the electric power generated by the electric power generating portion. The reader includes, e.g., a radio wave supplying portion for supplying the radio wave toward the temperature measuring pad, a receiving portion for wirelessly receiving the temperature information from the temperature measuring pad, and a storing portion for storing the temperature information.