Abstract: To meet the technical requirements as specified for a marine pipe project,the X65MO high-performance SAWL pipe that presents far better performance than the specification of API Spec 5L and DNVGL-ST-F101 is researched and developed.Described here in the essay are the main aspects of the pipe,including the chemical composition and properties of the steel,the technical requirements for the project,the manufacturing process and the trial product performance,etc.It is concluded via relevant analysis that at 0℃,the average values of the weld impact energy at the center of the wall and at the fusion line are much higher than the requirement as specified under the project;the tensile strength of the weld is equivalent to that of the base metal;at-40℃no ductile brittle transition is developed in the HAZ;and moreover no obvious softening occurs in the HAZ.