In view of the long transmission distance, wide coverage, easy to be afected by natural environment and human factors , which bring difficulties to the operation and maintenance of transmission lines, combined with the advantages of virtual reality ( VR) technology and geographic information system ( GIS) technology, a visual inspection system for transmission lines based on GIS technology and VR technology is proposed. This paper focuses on the research of transmission line fault detection method, which mainly collects transmission line image by UAV, and realizes the inelligent detection of fault components by establishing the network model of transmission line fault recognition and detection. The accuracy of the model is verified by experiments. The results show that the model can ffectively detect common components in transmission lines. Finally, the system is implemented by using GIS and VR development tools , and the actual effect diagram is shown. This study provides some reference for the development of visualization of transmission line inspection in China.