The long-distance oil and gas pipeline has a long transportation distance, and the terrain is complex and diverse. The frequent occurrence of geological disasters along the way will cause serious threats and damage to the safe transportation of oil and gas pipelines. In this paper, taking the lateral landslide of a Lian-Luo gas pipeline as an example, the dynamic response of the pipeline under the action of the landslide is analyzed through the unidirectional coupling method of discrete element and finite element. Firstly, the EDEM discrete element software was used to simulate the dynamic impact process of soil particles on the pipeline during the landslide process, and the changes of contact state and stress between the soil particles and the pipeline in the process of landslide were analyzed. Then the maximum landslide thrust experienced by the pipeline was imported into ANSYS as the load, and the stress and displacement distribution of the pipeline under the synergistic effect of the landslide and internal pressure was simulated. Finally, the simulation results were compared with the online monitoring data. The results indicate that the stress time history curve of the gas transmission pipeline under the action of landslide was obtained by discrete element simulation, and the pipeline received the maximum landslide thrust in the third second. Imported it into the finite element simulation to obtain the equivalent stress, shear stress and displacement distribution cloud map of the landslide section pipeline. Comparing the equivalent stress with the actual monitoring data, the relative error was less than 7.30%, which shows that the model has certain reliability.