Abstract: Aiming at the ultra-high requirement that the temperature stability of the gravity gradiometer as a satellite payload be better than ±10 mK/200 s, a comprehensive thermal control scheme was proposed including the construction of a component-level resistance-capacitance filtering network, the enhanced design of system-level thermal insulation, the multi-stage high-precision active temperature measurement and control, and the reduction of cable heat leakage. The thermal simulation analysis and thermal balance tests were carried out. It is shown that the temperature stability of the gradiometer components is better than ±8 mK/200 s, which meets the design requirements. The feasibility and effectiveness of this thermal control design method were thus verified. It may provide a reference for the thermal control design of other spacecraft parts with high precision and high stability temperature control requirements.