Aiming at the problem of control surface redundancy and vertical-longitudinal channel coupling in the tilting process of unmanned tilt-rotor aircraft, this paper analyzes the allocation strategy of redundant control variables and the fusion strategy of vertical-longitudinal channel control variables in the tilting process. The attitude controller based on linear quadratic regulator (LQR) is designed and verified. 2 sets of LQR-based multi-loop controllers were synthesized with the nacelle tilt angle as the weighting factor, and optimized by gain scheduling to overcome the problem of poor control effect caused by the difference of model characteristics in the tilt process, and the attitude smooth control of unmanned tilt-rotor aircraft in the tilt process was realized. Finally, the full-mode flight simulation of “helicopter forward flight-tilt transition-fixed-wing cruise” was carried out. The results show that the control system can effectively solve the problem of rudder redundancy and channel coupling, and the system performance is better in the tilting process.