In view of the problems of electromagnetic interference, power supply instability and short service life of existing transmission line condition monitoring devices, this paper develops an integrated condition monitoring system of transmission lines based on fiber bragg grating sensors. This system uses fiber bragg grating strain sensor, tension sensor, temperature sensor and vibration sensor to measure the tower strain, wire tension, wire temperature and Aeolian vibration, and sends the optical signals to the fiber bragg grating demodulator of the substation through OPGW. This system can realize the passive measurement of the running condition of the wire, and there will be no power supply problems. In addition, combining with the characteristics of anti-electromagnetic interference and high precision of the fiber bragg grating sensors, the stability and reliability of the system are improved.