InxGa1-xAs epilayers (x < 0.2) have been grown on GaAs substrates by atmospheric pressure OMVPE. The effects of varying the substrate temperature and the gas composition on the properties of the epilayers were investigated. The investigations have shown that higher mobilities were obtained at low growth temperatures (610°C), while optimum optical properties were obtained at higher growth temperatures (690°C). Variation of the AsH3 overpressure yielded optimum electrical and optical properties at a V/III ratio of 50. 77 K mobilities higher than 42 000 cm2/V.s and photoluminescence linewidths as low as 4.4 meV were obtained for x = 0.087 and x = 0.137 epilayers, respectively.