Very thin Nylon 11 films (less than or equal to 20 nm in thickness) containing Au nanoparticles were prepared, and current-voltage (I-V) characteristics in the vertical direction of the films were studied. The plan and cross-sectional transmission electron microscopic images revealed that Au particles are spontaneously aligned in the middle of the upper and lower electrodes and Nylon 11 tunneling barriers are naturally formed between Au nanoparticles and electrodes. Clear Coulomb staircases were observed in the I-V characteristics.