In the process of monitoring the state of the optical cable along the road,in order to avoid affecting the accuracy of the condition monitoring due t o the difficulty of the wavelength separation of the optical signal,this study uses the optical wavelength division multiplexing process to implement different wavelengths of light on the basis of the optical signals collected at the on-s i te monitoring station.Signal separation processing.According to the separation result,the distance between the monitoring point and the fault point of the op tical cable is obtained through the OTDR test,and combined with the wavelet tra nsform process to determine the maximum fault attenuation information.Based on this,the BP algorithm is used to locate the fault points in the ultra-long-di st ance optical cable along the path,and to monitor the status of the optical cabl e along the path.In the process of monitoring the state of the optical cable al ong the road,in order to avoid affecting the accuracy of the condition monitori ng due to the difficulty of the wavelength separation of the optical signal,thi s study uses the optical wavelength division multiplexing process to implement d ifferent wavelengths of light on the basis of the optical signals collected at t he on-site monitoring station.Signal separation processing.According to the s e paration result,the distance between the monitoring point and the fault point o f the optical cable is obtained through the OTDR test,and combined with the wav elet transform process to determine the maximum fault attenuation information.B ased on this,the BP algorithm is used to locate the fault points in the ultra- l ong-distance optical cable along the path,and to monitor the status of the opt i cal cable along the path.The experimental results show that the monitoring time of this method is always kept within 4min,and the fault location accuracy is a bout 80%.It proves that this method is short in the monitoring process,high in efficiency,and high in the fault location accuracy,which greatly improves the accuracy of state monitoring results.