Abstract: The Wuling Mountains in western Hunan are characterized by steep slopes, deep valleys, dense vegetation, and the terrain and geological conditions are complex. The majority of the Zhangjihuai Railway route runs parallel to the regional tectonic direction, and there are a series of engineering geological problems such as complex karst and karst water, weak and fractured rock masses, and widely distributed collapses (dangerous rock masses). Geological disasters occur frequently in the area. As a result, surveying, designing, and constructing high-speed railways in this area are extremely difficult. During the survey and design stage, comprehensive survey, special geological work, and geological route selection were carried out to avoid high-risk and difficult to handle unfavorable geology; appropriate engineering measures, optimize and adjust on-site were taken to ensure project safety. For karst and karst water, a special survey was carried out to investigate the distribution of karst along the line, and the route selection principle of "avoiding and walking high" was followed to minimize the risk of karst. Research was also conducted on the identification of karst water, acquisition of characteristic parameters, and evaluation of sudden water inrush in karst tunnels. During the construction period, comprehensive geological prediction was used to control construction risks, and comprehensive treatment plans such as reserving water passages and reinforcing and backfilling the foundation were adopted for the revealed large karst cavities. Select the plan with the smallest impact range for crossing faults in weak and fractured rock masses, and avoid long and deep buried soft rock tunnels by adjusting the horizontal and vertical sections. Measures such as surface sleeve valve pipe grouting and pipe shed advanced support were taken to reinforce the rock and soil mass and control tunnel deformation. During the geological route selection stage, the large-scale collapses (dangerous rock masses) were passed around. The remaining small dangerous rock masses were reinforced according to the design principle of "clearing, consolidating, and preventing". There were no engineering accidents during the construction process of this project, and the project has been in good condition since its operating. This railway line had established a"full-scale, full-process, and three-dimensional" survey and design system, which could serve as a valuable reference for the construction of the Qian-Ji Railway and Shi-Zhang Railway in the Wuling Mountain Area.