Research purposes: This paper comprehensively analyzes and studies the formation lithology,geological structure,the hydrogeological characteristics and the unfavorable geological conditions of the Qinling Mountain area along the Xi 'an - Chengdu Passenger dedicated line to define the railway alignment in the area with the better geological condition .
Research conclusions: For the railway alignment of the passenger dedicated line in Qinling Mountain area ,the geological conditions in the formation lithology,geological structure,the hydrogeological characteristics and the unfavorable geological conditions of the area in the research range were found out,and the adaptability of the different construction plans to geological conditions in the fields of the track plane position and gradient were analyzed. The comparative analysis of the different construction plans of Xi'an - Chengdu Passenger Dedicated Line in the Qinling Mountain area showed that the CK plan was better than the others in geological conditions,and the adaptability of the CK plan to geological condition in the fields of the track plane position and gradient was better than the others.