The half-shell gold particle film was fabricated by nanolithography and self-assembly monolayer technique. The structures and the unique optical properties of the films were studied by scanning electron microscope and spectrometer. It was found that the localized surface plasmon resonance effect was determined by particle size and the inter-particle distance. The peak extinction wavelength is sensitive to the surrounding dielectric constant. The experimental results showed that the structure uniformity is the key to obtain stable optical properties.