With the rapid development of the railway industry, higher requirements have been put forward for the quality and efficiency of railway vehicle maintenance and repair. Micro vision industrial endoscope inspection is a visual inspection method that controls the quality of areas where human vision cannot directly observe in special environments such as containers, pipelines, the interior of non removable equipment, and the inner surface of narrow gaps. It can reflect the situation of the tested object on the display for reference by inspection personnel through CCD imaging technology and lighting technology. With the continuous development of high-speed railways, endoscopes are also increasingly used for endoscopic inspection of various types of CRH vehicles on foreign high-speed railways and domestic CRH. From TGV to ICE, from Changchun Bus Factory to Qingdao Sifang, from Dalian to Zhuzhou, endoscopes have demonstrated indispensable importance in high-speed train gearbox detection, ventilation systems, internal castings, and other aspects.