Abstract: The paper introduces principle of special resistance welding,which is a new technology used in the welding of zirconium tube.The numerical simulation of three-dimensional temperature field of special resistance welding was analyzed with ANSYS.Using non-uniform meshing principle and parametric design language APDL to finish flow settings.The transferring effect of convective heat and radiation heat and temperature influence on material performance parameters is taken into account.Research results show that centralized heat flow causes the generation of coarse plug and extruded material.The temperature of weld joint is about 1 500℃,which has not reach its melting temperature.Showing hot forging structure with good mechanical properties.The temperature variation of radial direction and axial direction in the weld joint are both smaller than 5%.