Abstract: For the real-time simulation of the aero-optical transmission effect induced by the instantaneous fluctuation flow field, a novel method based on digital chaos was proposed. Firstly, the fluctuation flow field was decomposed into coherent structure field and completely random field according to the triple decomposition theory of turbulence. Secondly, Spheres generated by digital chaos were placed randomly throughout the volume with a chosen size distribution to represent one realization of the coherent structure field, and then the optical path length was calculated for all rays to produce the phase change. After that, the phase change of the completely random field was created by digital chaos. Finally, the random phase screen of the fluctuation flow field was reconstructed with the phase change of the coherent structure field and the completely random field, and physical optics method was adopted to get the corresponding point spread function(snapshot image), and so on to produce a large number of short-term and long-term sequence images. The simulation experimental results show that the method is in line with the wind tunnel experiment data. The method can simulate the aero-optical transmission effect under different flow conditions by adjusting the relevant parameters, and provides a new approach to assess and correct the aero-optical effects.