Abstract: To define the materials of a long-distance pipeline in China that is located in long spans permafrost area, X52 and X60 pipelines are analyzed for their resistances, combining pipeline failure causes and failure types and limit state, and by adopting the concept of pipeline reliability design, on the basis of the comparisons of conventional economic and technical schemes. It is considered that the whole resistance level of X52 pipe with 9.5 mm wall thickness is significantly higher than that of X60 pipe with 8.7 mm wall thickness; with the exception that these two grades share the same ability to against the third-party excavation damage and piercing, X52 steel pipe has obvious advantages in other aspects of performances, especially the ultimate tensile strain and compressive strain which increase by 17% and 31% respectively. Using uncertain parameters of materials, construction and operation maintenance, the failure probability levels under conditions of the third-party mechanical excavation damage and corrosion of X52 and X60 pipelines are quantitative calculated by Monte Carlo method. Results show that the failure probability of X52 pipe is far less than that of X60 pipe. Taking the pipeline safety reliability into consideration in the case of cost increases about 3.5%, X52 pipe with 9.5 mm wall thickness is recommended.