Butt resistance welding of super duplex stainless steel type 329J4L with inserting type 316L stainless steel wires was investigated. When the base material temperature was increased from room temperature to 1373 K at the heating rate of 550 K /sec, base materials were jointed through the insert wires. HAZ (heat affected zone) of the joint interface were less than 80 μm. In this jointing technique, the insert wires played an important role of concentrating current on the wires and increasing their temperature up to melting point or near melting point. Thermal analysis using thermography revealed that insert wires were adequately heated just after current started at a load of 10 N. When the welding was performed at a load of 70 N, joint area was increased by plastic deformation of the base material. That led to decrease of current concentration. Consequently insert wires were jointed in the solid state.