First-principles calcualtions of the magnetocrystalline anisotropy energy have been performed and it is predicted that the perpendicular magnetic anisotropy energy of a Au(Fe-Co)(111) multilayer will be larger than that of a Au/Co multilayer. Then we have actually synthesized the Au/(Fe-Co) multilayers by MBE method and found that theses multilayers show the predicted properites. The surface magnetic anisotropy energy is $0.64mj/m^2$, which is larger than the value reported previously for the Au/Co multilayer by 10%. Ther result indicated the possibility to control the magnetic anisortopy by changing the number of valence electrons.