In order to accurately predict heat transfer characteristic of long-tail nozzle in solid rocket motor(SRM), a numerical model was established for the long-tail nozzle composed of metal and several non-metallic materials using fluid-solid coupling method, unsteady heat transfer was calculated for the model based on CFD code FLUENT in this paper.Numerical results show that the heat of gas transfers from inside to outside in long-tail nozzle, but regional temperature field is different in external surface because of inner materials.The analysis results show that the computation values are basically identical with testing results in external surface.The method can provide a useful and convenient method for long-tail nozzle heat transfer analysis.