The Lan-Yu Railway will be a rapid and convenient trunk passage connecting the southwest and northwest regions. The construction of Lan Yu Railway has very important meanings as follow?ing； to improve the structure of railway networks in China develop resources along railway line, fun-damentally transfer poor to rich situation for people in the region promote cooperative development of economy within both Yangtze River and Huanghe River basins, realize national strategy towards West Region and its sustainable development, etc. The paper analyzes the situation of south-north railway trunk passage in China and the resources along the railway line. The authors propose also their opin?ion and suggestion for constructing the Lan-Yu Railway.