Abstract: The vibro-acoustic analysis of large and flexible structures is challenging and time-consuming under the frame of the conventional finite element method (FEM). To solve this problem, this paper proposes a method based on the statistical energy analysis(SEA) for the mid- and high-frequency vibro-acoustic analysis. The dependency of the internal loss factor on the model is determined in the case of a satellite antenna reflector. It is shown that the analytical result agrees quite satisfactorily with the test data when the internal loss factor ranges from 0.1% to 1.0%, and an assignment of 0.5% is advisable. This study may provide a helpful reference for the dynamic analysis of satellite antenna structures in the development process.