<p>A predefined-time pose control scheme equipped with a fixed-time disturbance observer is devised within the twistor framework to handle the integrated pose control of dual spacecraft formation. First, the six-degree-of-freedom relative motion of spacecraft is represented through twistors. Second, a predefined-time convergent sliding surface and a sliding mode controller are proposed based on the twistor-based model via Lyapunov stability theory, which can drive the follower spacecraft to the desired state relative to the leader spacecraft within a predefined time. Third, a fixed-time disturbance observer based on bi-limit homogeneous theory is introduced to estimate the lumped disturbance, and then the switching term of the sliding mode controller is replaced by the estimated disturbance to eliminate chattering while remaining robustness. Finally, the effectiveness of the proposed method is demonstrated by numerical simulations.</p>