The invention puts forward a fixed time convergence anti-interference control method capable of aiming at the return flight of a vertical take-off and landing reusable rocket. The method comprises thefollowing steps that: S1: establishing the return gesture control state equation of the vertical take-off and landing reusable rocket; S2: designing a fixed time convergence disturbance observer; S3:designing a tracking differentiator; and S4: designing an anti-interference controller based on the fixed time convergence disturbance observer. By use of the method, a buffeting problem brought by discontinuous control items in slip form control is eliminated, meanwhile, observer parameters are regulated so as to balance system convergence rate, robustness and accuracy requirements and reduce aninfluence caused for the control system in an observer regulation process, and therefore, the method has a wide application prospect in designing the return flight attitude controller of the verticaltake-off and landing reusable rocket.