A series of Au and Ag films was deposited on the Dove prisms with different refractive indices. By this solid contacting configuration, it was found that the spectra of dielectric function measured at the metal substrate interface do change with the refractive index and differ from those measured at the metal air interface in both the Drude and interband transition regions. This phenomenon may be explained by the surface optical properties of the noble metals, which will strongly depend on the ambient. The reconstruction of the surface state related to the different medium may account for the effect that should be taken into consideration in the optical and magneto optical applications involving metallic multilayer film structure design.