InP film samples were prepared by spray pyrolysis technique using aqueous solutions of InCl 3 and Na 2 HPO 4 , which were atomized with compressed air as carrier gas onto glass substrates at 500°C with different thicknesses of the films. The structural properties of the samples have been determined by using X-ray diffraction (XRD). It was found that the crystal structure of the InP films is polycrystalline hexagonal. The orientations for all the obtained films are along the c-axis perpendicular to the substrate. It is observed that the crystallite sizes of the films increase with the thickness of the film up to 616nm. The changes observed in the morphology and structural phases related to the film thickness have been discussed in detail.