Abstract: Wire arc additive manufacture on copper/steel composite joint test was carried out by using the technology of bypass-current wire-heating Plasma Arc Welding (PAW) on additive manufacturing. 304 stainless steel and S201 copper wire selected as deposition metal. The effect of surfacing sequence on forming was analyzed, and the interface microstructure and mechanical property of the copper/steel composite joint were also investigated. The results show that under the sequence of addition copper and steel, the collapse of the molten pool was effectively prevented and a well-formed copper/steel additive joint was obtained. The hardness and mechanical properties at the copper/steel interface were significantly improved due to the effect of Fe solid solution. The average tensile strength of the composite joint was 256.8 MPa. The fracture occurred on the copper side and the shrinkage of the section was 52.8%, and the elongation was 15.68% and the fracture form was of ductile fracture.