To meet the high-precision attitude control requirements of flexible satellites, this paper proposes an anti-windup H∞ control method based on a full-order dynamic observer to address the issues of composite disturbances and actuator saturation constraints during maneuvers. By leveraging the structural characteristics of the flexible satellite attitude system, an H∞ controller integrated with a full-order dynamic observer is designed through the application of Lyapunov stability theory and linear matrix inequality (LMI) techniques. Furthermore, an anti-windup compensator is developed based on the input-output characteristics of the actuator to mitigate input saturation effects without increasing the dimensionality of the control system. Finally, the validity of the method, along with its practical feasibility, is confirmed through numerical simulations.