Remote microgrids (MGs) with satellite internet feature a high degree of model uncertainties, which affects the system stability seriously. In this paper, an adaptive secondary control strategy is proposed for space–air–ground integrated remote MG systems to solve voltage recovery issues considering model uncertainties. Firstly, an adaptive law is designed for adapting to changing system parameters under various operation environmental conditions, based on which a backstepping control method is applied into remote MGs for voltage restoration. Then, by analyzing the resulting system through a Lyapunov function, it is demonstrated that space–air–ground integrated remote MG systems with the proposed control scheme is able to achieve voltage restoration even in the presence of model uncertainties. Finally, an islanded AC MG system with 4 distributed generators (DGs) is conducted on the MATLAB Simulink environment to validate the accessibility and effectiveness of the proposed method under the circumstance that all the system parameters are unknown.