The Qinghai-Tibet Railway intersects with many active fault belts distributed on Qinghai-Tibet plateau. In this paper, the distribution laws of 29 active fault belts along the railway and geological hazards caused by the faults are studied. Through analysing the characteristics of geological hazards such as collapse, landslide, debris flow, and tipical sections of the route line, some principles for geological route selection in fracture zones are summurized as follows： the route should be arranged to pass across active fault segment with weaker activities and narrower width of the belt in right angle or higher angle, avoid as could as possible to build large and medium-size bridge, high bridge, tunnel, high-filling, deep-dugging which are difficult to be repaird after dammage. It has been proved that these principles are right and feasible for avoid or pass the active fault belts, and can be used in rebuild of Qinghai-Tibet Railway or other railway project.