Abstract: The main goal of this paper is to analyze the displacement and stress of a supersonic fin on a transient dynamic load. The reduced order mode(ROM) based on Volterra Series is presented to calculate the flutter boundary, and CFD/CSD coupling is used to calculate the transient aerodynamic load. Transfer the load to a structural model by using FEFN (finite element four nodes) in a parametric space for a transient response analysis. The results show that due to the aerodynamic load and the inertia force through vibration, the maximum bending stress on the root of the axis is about 3 times than the stress induced by static aerodynamic loads.