Aiming at the controlling of trajectory during the air-to-ground attack, firstly, the 6-DOF model of combat aircraft and the model of the threats are established. The thrust coefficient, angleof-attack, and roll angle are chosen as the controlled quantity. Then establish the indicator function and the optimum control modelling of the air-to-ground trajectory decision-making. Adopt the RHC-PSO algorithm, getting the controlling quantity's optimum value in every decision-making time domain, combining the RHC to realize online controlling of trajectory. Simulation shows that the algorithm can control the aircraft to perform the operational mission and show the change law of the controlled quantity, giving the information of aid decision making to pilot.