The InGaN/GaN films were grown on (0001) sapphire substrates by metalorganic chemical vapor deposition (MOCVD) at atmospheric pressure. Properties of these films were investigated by Rutherford backscattering/channeling measurements and photoluminescence technique. The study indicated that there was an optimum TMIn/TEGa ratio to obtain high In mole fraction In x Ga 1-x N films. The In mole fraction in In x Ga 1-x N films will increase by decreasing the TMIn/TEGa ratio in some range. Surface minimum yields χ min of In x Ga 1-x N films changed from 4.1% to 11.0% when the x value of In x Ga 1-x N varied from 0.04 to 0.10.