Abstract: The principle of a new optical fiber temperature transducer is presented, and ingenious design scheme of this transducer is given. Because taking the special modulation and ratio measurement, this new transducer has provided with high characteristics: experimental transmitting distance is 500 m; measurement error, in the measured temperature range of 0~250℃ , is less than ±0.5 ℃ ; power consumption of the probe is less than 30μW. Finally, some points of the experiment are given. Because of the special modulation and ratio measurement, this new transducer has provided with high characteristics: error, in the measured temperature range of 0-250 ° C, is less than ± 0.5 ° C .; power consumption of the probe is less than 30μW. Finally, some points of the experiment are given.