Abstract: A distributed formation control method is designed based on the extend state observer, auxiliary system, and command filter for air-ground heterogeneous multiagent systems（HMASs）with unknown external disturbance and input saturation. Firstly, the model of the HMAS is constructed by converting the model of the quadrotor unmanned aerial vehicle and the unmanned ground vehicle. Then, an extended state observer is designed to estimate the unknown external disturbance. To solve the input saturation problem, auxiliary system is constructed. On this basis, the distributed air-ground formation controller is designed based on the backstepping technology and the command filter. Besides, the convergence of all closed-loop signals is rigorously proved by the Lyapunov theory. Finally, the effectiveness and feasibility of the distributed formation control method is verified by simulations.