This application relates to a method of preparing a composite material for an electric wiring connector. In one embodiment, the method includes preparing a powder mixture including (i) a metal powder composed of aluminum or aluminum alloy particles and magnesium particles and (ii) a polymer powder. The method may also include sintering the powder mixture to produce a composite material for the electric wiring connector using a spark plasma sintering (SPS) process. This application also relates to a composite material for an electric wiring connector prepared through the method described above. This application further relates to a method of manufacturing an electric wiring connector, the method including forming a housing of the electric wiring connector with the composite material. This application further relates to an electric wiring connector manufactured by the method.