Abstract: This paper discussed the attitude and drag-free control of two Earth-orbit drag-free satellites with two test masses. The control schemes of the science mode were designed, and a robust controller capable of resisting disturbances was proposed. First of all, based on the science requirements and the LEO characteristics, the configuration scheme for the science mode was designed, to present a stable observation platform for the detection mission. Secondly, decoupling the complex system dynamics model based on characteristics of dynamic coupling and control time-frequency, three loops—the spacecraft attitude control loop, the drag-free control loop and the suspension control loop—were produced. Control requirements for each loop were specified according to mission requirements. Thirdly, taking into account the control requirements in frequency domain and the spectral models of various external disturbances and sensor noises, constrains for sensitivity functions and complementary sensitivity functions of each control loop were derived utilizing the mixed-sensitivity method of H _∞ robust control theory. By selecting appropriate weight functions, an H _∞ robust controller was designed. Finally, simulation results indicate that not only the inter-satellites pointing error but also the pose errors and residual acceleration of test masses satisfy the control index requirements, which verifies the effectiveness of the designed controller.