Abstract: Rockfall is one of the major geological hazards causing pipeline failure in southwest mountainous areas.With the increase of service life of oil and gas pipelines, the corrosion problems of long-distance pipelines are inevitable, and the combination of rockfall impact load and pipeline defects greatly increases the risk of pipeline failure.According to the relevant parameters of the West-East gas transmission line, ABAQUS software is used to establish a model of rockfall impact buried pipeline with internal corrosion.The response dynamics of the pipeline is explored by changing the internal pressure, internal corrosion defect size, overburden depth and wall thickness of the pipeline.The results show that the buried pipeline stress is less affected by the defect length and defect width; the pipeline internal pressure, defect depth and rockfall impact velocity have a greater impact on the pipeline, of which the deepening of the defect is more likely to cause the critical failure of the pipeline.The measures such as increasing the depth of cover and pipe wall thickness can effectively improve the overall pipeline safety, but still need to consider the effect of the depth of cover and pipeline consumables on the investment and maintenance costs.