The rockfall has threatened the safety of the pipeline when the natural gas pipelines pass through the mountainous area. The main landslide prone areas represent a threat against the pipeline system. They are identified and their landslide hazard needed to assess. In the study, the finite element model of the different sizes of rockfalls impacting buried pipeline was established in ANSYS Workbench. Based on ANSYS/LS-DYNA with the basic theory of nonlinear dynamic mechanics and dynamic calculation method, in the semi-infinite soil medium, by setting dynamic and contact parameters suitably, based on choosing suitable constitutive relation, the vibration rule of buried gas pipeline is gained by the numerical simulation analysis. The study obtains the physical process of intrusive rocks and soil and the stress of gas pipeline. Also the study gets the damage of the different rockfalls impact accident. By the way of finite element software ANSYS, the study calculates pipe stress under landslide deposits of rock by contact problem, and determines the maximum Mises Stress Criterionand failure length. The results provide the basis the data of estimating for the damaged the high pressure gas pipeline.