The utility model provides an electrothermal welding welding pipe fitting of ultrahigh molecular weight polyethylene pipeline reserves the pipe at the spiral groove of two sets of series connection, two sets of series connection spiral groove's both ends and reserves two through wires holes respectively on the electrothermal welding ferrule inner wall, set up among the spiral groove of two sets of series connection respectively through resistance wire positive electrode tab, resistance wire negative electrode connector in the resistance wire of series connection, two through wires holes, spiral groove's the degree of depth sets up the half into the resistance wire diameter, infusible section is reserved respectively at the infusible section of reservation, two sets of spiral groove both ends between two sets of spiral groove of electrothermal welding ferrule inner wall, and infusible section sets up the support ring into the electrothermal welding ferrule, the utility model discloses a direct suit, is stereotyped by the infusible section between the ferrule inner wall resistance wire winding through the resistance wire sweat soldering between pipe connector and the pipeline at the seam crossing of pipeline, welds internal stay, simple to operate without tubular product for the product percent of pass has been improved in submarine pipeline, salt lake, chemical industry field and can not excavate the pipeline.