The effect of Zr, Mo and Y adding on mechanical and electrical properties of Au-Pd, Pt-Ir and Pd-Ru systems was investigated. The alloys were prepared in a vacuum high frequency melting furnace. X-ray diffraction and metallographic microscopy were employed to detect the microstructures. Electric bridge and eddy current conductive instrument were used to test the electrical resistivity, and the mechanical properties of the alloys were tested by AG-X100KN type tensile testing machine. The results show that adding of rare metal elements in Au-Pd, Pt-Ir and Pd-Ru systems could refine structures of the alloys effectively, increase their melting points, densities and electrical resistivities, and improve mechanical properties of the alloys, but the elongations of the alloys is decreased.