Abstract: The article summarizes the major engineering geological problems existing in Dali-Lincang Railway and Yuxi-Mohan Railway which are building now, and the newly-built Lincang-Qingshuihe Railway and Dali-Lanping Railway. In western Yunnan, there are complex structures, active faults, engineering geological problems such as landslides, mudflow, high ground temperature, high stress, karst, radioactivity, harmful gases, benefic layers, and there are swelling rock(soil) and soft soil distributing in the fault basins. The article serves as a reference and guide for railway construction in the western Yunnan or similar geological conditions.