As for the linear systems with multi-source disturbancesa two-level optimal setting control method based on disturbance observer is studied.For the disturbances without a complete and accurate modela disturbance observer is designed.For the norm-bounded external disturbances which cannot be described by the disturbance observera dynamic optimal setting control scheme is provided.According to the observation value of the disturbance observerthe set value is adjusted dynamicallyso that the controlled output can still track the set point under the action of the original controller when there are multi-source disturbances in the system.Numerical simulations have verified the feasibility and effectiveness of this method.