The development of the MEMS (Micro Electro Mechanical System) technology makes the COTS (Commercial Off-The-Shelf) attitude sensor smaller, enables lower power consumption, and improves the attitude determination and stabilization performance of the CubeSat. However, their performance has a temperature dependence. Verification and evaluation need certain development duration and costs. In addition, in CubeSat thermal design, the contact thermal conductance between the components can be varied with the system integration uncertainties and the thermal interfaces are difficult to standardize. Their heat capacities are small and the temperature of the component is easy to be influenced by the thermal environment changes mainly corresponding to their attitude. This paper proposes the temperature stabilization system for MEMS attitude sensor for maintaining performance. The system mitigates temperature change by increment the heat capacity around the target temperature. The novel solid-solid phase change heat storage materials are introduced and evaluated for this purpose. In addition, the suitable insulator and heat transportation materials are designed and equipped to reduce the contact thermal conductance variation range. The effectiveness of the proposed system is confirmed through numerical analysis and some typical experiment, considering practical on-orbit condition. The thermal-mathematical model of the proposed system is also constructed through the discussions.