in this paper, A full-size bursting test of nature gas pipeline was carried out in the test site to simulate the pipeline exploding, and the influence of bursting on the adjacent pipeline was studied with a series of tests in the laboratory, including not only mechanical properties but also microstructure analysis. Deformation and heat effect was the main risk for the adjacent pipeline. The bending and flattening deformation for the adjacent pipeline occurred, the waving variations of ovalities for the pipeline cross section was found, and the properties and microstructure of the middle girth welding before and after the test was compared. The drop weight energy of the heated samples was measured to evaluate the influence of the jet flame, the microhardness along the thickness direction was given to study the depth of heated area. The microstructure of heated area was studied the effect of jet flame. The results showed that the maximum bending and flattening deformation occurred near the middle girth welding, and the properties and microstructure of the middle girth welding changed little during the deformation. The jet flame made the drop weight energy decreasing almost 16% and the surface hardness reducing. The phases coarsened, some pearlite appeared, and the orientation direction disappeared in the heated area. The depth of heated area was about 600?m, which showed jet flame did not last too long time.