Highly oriented nanocrystalline indium nitride (InN) films were successfully grown on Si(111) substrate. The growth rate of InN film can be enhanced fourfold by a double-zone metal organic chemical vapor deposition system consisting of a high temperature NH3 pre-cracking zone and a low temperature deposition zone. A maximum growth rate of 6 mum/h was achieved due to the high cracking efficiency of NH3. Meanwhile. the growth temperature of the substrate can be varied from 350 to 600 degreesC, which provides more flexibility for the film structure. While X-ray diffraction revealed the (0001) texture of the film, the high-resolution transmission electron microscopy study concluded the growth of highly oriented nanocrystalline hexagonal InN, which may lead to potential solar cell and optoclectronic applications.