Abstract：This paper applied metal cladding method to manufacture 2205 duplex stainless steel with carbon steel core HRB400. Thermal simulation experiments were conducted by geleeble-3800, the high temperature rheological curve and thermal processing diagram of 2205 stainless steel were studied. Finally, the rolling temperature of the composite steel rebar was determined to be ≥1150℃.Through numerical simulation of composite rolling, it is found that during rough rolling deformation, the strain is concentrated on the surface layer and 1/4 position of the rolled part. With the continuous infiltration of the deformation to the core, the stainless steel cladding layer where the plastic strain is larger is thinner. In the process of finishing rolling pass of K1, it is found that the thickness of the stainless steel cladding is the thinnest at the root of the transverse rib and the thickest at the crest of the transverse rib. Near the interface of composite rebar, the diffusion distance of Cr, Ni and Mo is 18-20μm, and the microstructure from carbon steel to stainless steel is ferrite and pearlite microstructure, decarburization microstructure, composite interface, austenitic stainless steel microstructure, ferrite and austenitic stainless steel microstructure.