Abstract: The butt-welding process on X65 and A105 pipe joint is introduced. This two steel pipe joints have different steel grade and strength. Based on experiment and analysis the weldability of the two joints, the preheating temperature is determined with rational welding material and bevel type. The welding process evaluation on the two joints is carried out on the basis of Q/SY XQ18-2002 《Station Process Pipeline Installation and Acceptance Code for West-to-East Pipeline Project》 and XQ-CS-JX-SPE-0010 《Station Pipeline System Welding and Inspection Technology Requirements》. The results show that the apparent inspection of pipe ends and X-ray detection are qualified with perfect indexes in metallography, tensile test and impact test.