Yunnan-Guangxi HVDC transmission engineering is one of the important West-East electricity transmission project in the twelfth five-yearSplan, and it is facing the circumstances of long-distance parallelism and crossing with China-Myanmar oil/gas pipeline. To alleviate the electromagnetic influence on this condition, the simulation study of electromagnetic effects on China-Myanmar oil/gas pipeline due to Yunnan-Guangxi HVDC transmission line was conducted. The computational model for the two crossings between these two projects was established using CDEGS software. Then the voltage distribution on the pipeline and coating of the pipeline caused by the power line on condition of normal operation, single-pole ground fault, and being struck by lightning was studied to make a quantitative evaluation of the degree of electromagnetic influence, and some suggestions for unqualified crossings were proposed by the comparison between calculation results with the limits. This research is of significant value to the safety operation of these two projects, and can also provide a quantitative guidance and technical support for HVDC transmission engineering and the oil/gas pipeline construction.