By application of clad-bonding technique of pure copper sheet and plain low carbon steel rebar Q195, the cladding wires in different diameter by drawing at room temperature have been worked. The increasing ratio of the area of grain boundary is in direct proportion to deformation approximately. The resistivity of the cladding wires go up in direct proportion to deformation because the increment of the area of grain boundary results in increment of static disfigurement to electron dispersion. When deformation is less 9.6, the relative increment of resistivity is less 1.1%, i.e. the wire is provided with good electrical conductivity. And the resistance and resistivity of the wires can be estimeted based on copper ratio of transverse section of the cladding wire and the deformation by drawing at room temperature.