Abstract: Based on the characteristic of laser warning system with non-imaging imaging mode, a double cylindrical lens system was presented. A new optimization method, based on the ray tracing of cylindrical lens, was introduced in this paper. Traditional single-cylindrical lens and cylindrical reflector systems were limited by FOV, less than 1, and low-quality line spot. This optical system, composed by two ZnSe cylindrical lenses, meets the operating wavelength of 1.0-4.0 m and achieves a 20FOV and the modulation transfer function(MTF) is better than 0.7 at 7 lp/mm on the edge of FOV. This optical system achieves the requirement of laser warning system with non-imaging mode.