China-Myanmar oil & gas pipeline project covers 7,676 miles in all. The project met with complex geological conditions, construction types along the line, and long-distance oil & gas parallel laying pipeline. Because the pipeline layout and the construction are more complicated, it is necessary to make the stress analysis of oil & gas parallel laying pipeline traversing tunnels. Software CAESAR II is used to make numerical simulation on one section of oil & gas parallel laying pipeline. Through analysis we can get the main load infector effecting oil & gas pipeline stress, and the location of the most dangerous section. In the end, some feasible suggestions can be put forward for the security of oil & gas parallel laying pipeline according to the analysis conclusion.