The invention discloses a near-space aircraft control system, which belongs to the technical field of aviation aerospace propulsion control. The near-space aircraft control system aims at the attitudestable tracking control problem of a near-space aircraft, and considers the problems of unknown interference and parameter uncertainty. According to the near-space aircraft control system, firstly, an estimated value of an interference observer for interfering the outside world, then the parameter uncertainty of the aircraft is analyzed, and a self-adaptive estimated value of the aircraft parameters is obtained; secondly, an integral sliding mode surface is selected thus a self-adaptive integral sliding mode controller is designed for tracking control of an inner ring attitude angle of the near-space aircraft; and finally, the stability of the controller is proofed by utilizing a Lyapunov stability theory. The near-space aircraft control system can ensure the global stability of a closed-loop system, and enable the system to have good tracking performance and robust performance.