Abstract: Restricting the engine maximum rotor speed based on nonlinear forecast was studied.The dynamic process was described by the Volterra series model,and then the nonlinear close loop forecast model was established.According to the input constraints and control objective,the roll control algorithm of rotor speed forecast restriction was proposed.The simulation was carried out.The forecast restriction curve of fuel flow change versus rotor speed under the excess fuel flow during acceleration was obtained.Compared with the proportion feedback restriction,the forecast restriction can be used to avoid the affection of fuel burning delay and engine inertia,and to realize the rotor speed restriction accurately.As the volume of calculation is less,it fulfills the real time requirement.