Plastic deformation of sprayed alloy is an effective method to fabricate the hypereutectic aluminum-silicon alloy which combines good conductivity and toughness. In this study, Al-20Si-0.35 RE (wt%) alloy was synthesized by spray atomization and deposition technique. The sprayed deposition and over-spray powder were hot-extruded and plastic deformed respectively. Microstructure and conductivity were systematically performed in order to understand the influence of deformation on microstructure and conductivity of the hypereutectic alloy. The Si particles are refining and uniformly distributed in the Al matrix due to the proper addition of rare earth metal and the rapid solidification preparation method. The microstructure of plastic deformed alloy has invariably indicated that severe plastic deformation lead to the even refinement of microstructure. Both the conductivity of over-spray powder extrusion and sprayed deposition extrusion were obviously improved after plastic deformation. Possible mechanisms of deformation on microstructure and conductivity of hypereutectic aluminum-silicon alloy are discussed. Plastic deformation of sprayed alloy is an effective method to fabricate the hypereutectic aluminum-silicon alloy which combines good conductivity and toughness. In this study, Al-20Si-0.35 RE (wt%) alloy was synthesized by spray atomization and deposition technique. The sprayed deposition and over-spray powder were hot-extruded and plastic deformed respectively. Microstructure and conductivity were systematically performed in order to understand the influence of deformation on microstructure and conductivity of the hypereutectic alloy. The Si particles are refining and uniformly distributed in the Al matrix due to the proper addition of rare earth metal and the rapid solidification preparation method. The microstructure of plastic deformed alloy has invariably pointed that severe plastic deformation lead to the even refinement of microstructure. Both the conductivity of over-spray powder extrusion and sprayed deposition extrusion were obviously improved after plastic deformation. Po ssible mechanisms of deformation on microstructure and conductivity of hypereutectic aluminum-silicon alloy are discussed.