Abstract: In view of problem that existing tension measuring methods of round link chain of scraper conveyor could not detect tension of round link chain in real time by using wired method, a wireless tension sensor of round link chain of scraper conveyor based on RFID was designed. The sensor uses resistance strain gauge as sensitive element, strain signal detected by resistance strain gauge is converted to voltage signal relating to tension signal through bridge strain measurement circuit. The voltage signal is sent to nRF24LE1 after being magnified and filtered, and then it is sent to wireless collection substation by wireless transmission module of nRF24LE1, so as to realize real time wireless measurement of tension of the round link chain and the data wireless transmission. According to the real time tension and tension changes situation of round link chain, the sensor can judge the degree of tightness of round link chain, and can effectively forecast and truly determine broken chain fault. The experimental results verify the reliability of the sensor.