Abstract: To address the problems in realistic rendering of butterfly iridescences in computer graphics,this paper proposes a photorealistic simulation method,based on the thin film interference model.The method firstly constructs the multilayer film model,according to the ridge microstructures on butterfly wings; then it applies the multilayer film interference principle to model the mixed scattering characteristics of multiple reflections and transmissions of light inside films; The Fresnel formulae is employed to explain the amplitude variations of reflected or transmitted wave,and the microfacet scattering factor is creatively incorporated to model the anisotropic properties of rough surfaces of butterflies; finally,we augment the interference effects by full wavelength spectrum modeling and further combine the method with a ray tracing framework to construct the wave bidirectional scattering distribution function interference model,to accurately render the amplitude and phase variations of light.The experimental results demonstrate that our method can efficiently model the photorealistic iridescent colors of butterflies.