Abstract: Currently, most routes of the oil and gas pipelines in mountainous areas are selected in a traditional manual manner, with the quality greatly depending on the experience and technical level of the route selection personnel. Thus, the result of route selection is often not scientific and reasonable enough. Therefore, a route selection method of oil and gas pipelines in mountainous areas based on geological information atlas was put forward. Specifically, the regional geological information atlas is established in terms of landform, geological risk, high consequence area and sensitive area, the cost grid map for route selection through the quantification of factor cost is built with consideration to the routing cost of pipeline, and thus the optimal route is obtained through the analysis with optimal route algorithm. In addition, this method was applied to a pipeline in the mountainous area in Southwest China. By comparing the calculated route and the existing route, it is found that the route analyzed by this method of pipelines in mountainous areas based on the geological information atlas could effectively avoid the complex terrain, poor geological environment, high consequence area and environment sensitive area, and the distance cost could be considered comprehensively, thus solving the problem of inadequate consideration to the comprehensive factors in manual route selection. In general, the route selected by this method could be used as a reference for the pipeline route designers.