The spatial distribution of the interference of surface plasmon polariton (SPP) on metallic nanostructures has been studied. The results show that the transmission of electromagnetic radiation is remarkably enhanced for frequencies close to the surface plasmon band and the interference of SPP can redistribute the illumination light into subwavelength-scale spatial distribution with high intensity, which beats the Rayleigh diffraction limit. For an appropriate thickness, the transmission of an unperforated structure can be larger than that of holes or slits systems with the same periodicity and thickness when the coupled surface plasmon wave mode is excited. With the help of the interference of the horizontal plasmon excited by Bragg resonance due to the periodicity in the horizontal direction, the vertical plasmons, excited in z direction via Fabry-Perot cavity resonance in different grooves, are correlated, so the transmission is increased via the tunneling process. The properties of transparency for light but impenetrability for gas and liquid will be of importance for device applications. The information on nearfield distribution from perforated metallic structures is important for understanding the underlying physics, as well as for optimizing photonic crystals for possible applications.