Abstract: This research investigated the dynamic properties of a flying wing aircraft with high aspect ratio and strong coupling between the flight dynamics and the aeroelasticity, and the corresponding control method. The inertial coupling between rigid-body DoF motion and elastic DoF motion were addressed by free-free modes of the whole aircraft. The double lattice vortex method and the rational function approximation (RFA) method were used for unsteady aerodynamic calculation. LQR method was used for the combined control law design to control the flight dynamics and elastic deformation simultaneously. Compared with the uncontrolled case, the designed close-loop control law could effectively reduce 60% of the pitching angle disturbance. It can be concluded that there is significant dynamic coupling between the short period and the first bending aeroelastic mode. The combine control law can generate dynamic elastic deformation which is always helpful to disturbance alleviation in the dynamic process.