Silicate particles are synthesized by hydrolysis of ethyl silicate in the mixed solvents of ethyl alcohol and water under the catalysis of ammonium water solution. Scanning electron microcopy and laser light scattering spectroscopy show that the synthesized silicate particles are in perfect spherical shape and are monodispersed in sizes with their diameters of about 0.7 μm. These silicate particles can assemble themselves into photonic crystals on glass substrates. The eleventh order of diffraction can be observed when a beam of helium-neon laser is perpendicularly incident on the thin films of the photonic crystals formed by the silicate particles. Six-fold symmetric diffraction patterns are recorded when a beam of white light passes through the photonic crystals, suggesting that hexagonal close packing structure can be formed in the photonic crystal by the silicate particles.