Abstract: The recoil force from attack helicopter gunfire would cause the change of kinetic parameter of the carrying aircraft, and further affect the firing accuracy of weapon. Actually it is of a phenomenon on disturbance response. In order to reduce this recoil effects, a gun recoil compensation control framework based on nonlinear H_∞ method was put forward. First, according to the six-degree-of-freedom motion equations, the anticipated force and moment commands were derived by solving the Hamilton-Jacobi partial differential inequation. Then on the basis of helicopter aerodynamic force and moment formula, the anticipated commands were approached by using iterative algorithm until getting actual blade pitch commands. Finally the simulation was carried out with the combination of the flight control system and gun recoil parameters. It-s indicated that the control system can achieve good performance and stability robustness, and effectively attenuate the disturbance to aircraft.