: Presents the numerical investigation on optical transmission of the metallic film with subwavelength tilted edge silt structure by means of finite-difference time-domain (FDTD) method. The study shows that the transmission spectra are altered when the lateral displacements of 2-layer slits change. By analyzing the distribution of the electric field and electromagnetic energy, shows the mechanism of the two different resonances: the local waveguide resonance mode restricted inside the slits region and the surface plasma resonance mode while electric field and electromagnetic energy distributed at slits′ two ends.