In order to substitute a conventional fin operated by hydraulic actuators, a smart fin actuated by piezoelectric material was attempted. A straight unimorph actuator was embedded along the spanwise direction in the hollow inner space of the fin. A hinge which was constrained except the axial rotation was located at the 1/4th chord line, and this enabled the smart fin to rotate in its rigid pitch direction. In this paper, starting from the fundamental structural analysis, the aeroelastic and aeroservoelastic stability, and structural response simulations of the smart fin control system were performed by integration of MSC.NASTRAN, ZAERO and MATLAB/Simulink. The controller was designed to ensure the flight stability and to maintain the pitch angles of the smart fin under specific flight conditions. Closed-loop control system of the smart fin was constructed and analyzed by MATLAB/Simulink.