With the advance of computation technology and the increase of computing power, computational fluid dynamics (CFD) has been considered as an analysis method to complement the conventional wind tunnel test. This analysis method, however, still has issues with its reliability and accuracy. To assess the potential of CFD analysis usage in examining the aerodynamics of civil structures, this study conducted a preliminary study of 2D Fluid-Structure Interaction (FSI) analysis on a simple rectangular prism body. Model parameters in the form of heaving displacement and lift coefficient of the prism cross-section were evaluated in this analysis. The numerical model was validated by comparing the heaving displacements obtained from the analysis with existing wind tunnel test data. The simulation developed using ANSYS shows good agreement despite some differences. These results indicate that 2D FSI simulations could serve as a valuable complement to conventional wind tunnel tests. This approach may pave the way for a new, cost-effective assessment method that offers greater flexibility and enhanced data visualization compared to conventional wind tunnel experiments.