Research conclusions：The Dali-Baoshan section of Dali-Ruili Railway is nearby the colliding suture zone o f the Indian plate with the Eurasian Plate. As the terrain and geological conditions in this area are extremely complicated, the railway track is much affected by the geological disasters, such as active fault, seismic hazards, collapse , landslides, debris flow and high-temperature hot water. Based on learning the experiences o f alignment in the southwest mountainous area with vale cut sharp and active fault, the technical principles of alignment in Dali-Baoshan section are presented, and the north route scheme with better geological conditions is selected with the railway crossing the Lancang River through the Jihongqiao Bridge.