Abstract: A method of predicting pitch and roll damping derivatives of missile geometries with fins using an unsteady RANS(Reynolds-averaged Navier-Stokes) solver was presented.A three-dimensional structured RANS solver based on arbitrary Lagrangian-Eulerian(ALE) formulation with a dynamically deforming mesh algorithm was used and validated by the wind tunnel and ballistic range data available in the literature.Roll and pitch damping derivatives were calculated from load history of the unsteady flow around the model.A standard research configuration,known as the basic finner,was studied under forced pitching and rolling conditions.Pitching and rolling motions with oscillation were analyzed at supersonic Mach numbers ranging from 1.5 to 2.5.Predicted results show good agreement with the available wind tunnel data.