Transmission of laser optical elements has been increased when Indium tin oxide (ITO) thin film of relatively high index with different content of Sn was used to prepare ultra thin antireflection coating(ARC's) utilizing simple ,low cost non-vacuum chemical spray pyrolysis technique. Two plans were established to achieve the goal: theoretical transmission analysis of ITO film on glass was first carried on with the aid of TFcal software taking into account the effect of absorption, dispersion and ITO thickness variation on transmission profile. This step provides a clear vision and preliminary thickness range of ITO films before sample preparation with spray pyrolysis method. Results show that XRD spectra reveals that all the films were cubic polycrystalline. Both scanning electron microscope and atomic force microscope indicate that the surface roughness increase with Sn content. Thus , durable and adhesive antireflection ITO ultrathin film, of good transmittance profile was achieved at Nd-YAG laser line of 1.064 μm wavelength when preparation conditions were optimum control .