The low-velocity impact behaviors of aeroelastic functionally graded CNT (carbon nanotube) reinforced composite panels in supersonic airflow are investigated. Thermal effects are taken into account. Reddy's higher-order shear deformation theory is applied in the structural modeling. The effective material properties of the functionally graded CNT reinforced composite panel are calculated by the rule of mixture. The aerodynamic pressure is evaluated by the first-order piston theory. The contact force between the panel and the impactor is simulated by the Hertz law. Hamilton's principle and the assumed modes method are used to formulate the equation of motion which is then solved by the numerical method because of the high nonlinearity. A simplified mass-damping-spring model is also introduced to solve the problem. Influences of the aerodynamic pressure, CNTs distribution and volume fraction and thermal effects on the impact responses of the functionally graded CNT reinforced composite panels are investigated. The simulating results using the numerical model and the mass-damping-spring model are compared. The affect factor considering the inertial effect of the panel in the low-velocity impact for the CNT reinforced composite panel is given out.