Abstract: The polarization scanner is mounted on the satellite floor and surrounded by multiple other loads. Therefore, due to its complex thermal environment, it is of difficulty for satellite thermal control design. According to the thermal control requirements for each component of the scanner, a thermal control scheme was designed in this paper. The scheme includes: ensuring the insulation between main optics and the frame together with multiple layers of insulation components cladded; introducting independent heat dissipation paths for the infrared detector heat sink and the head circuit box, respectively, with an external heat pipe connected to the auxiliary heat dissipation panel; inplementing active temperature control electric heating; installing heat insulation pads in key areas. The thermal control scheme has passed the ground-based thermal balance test. Orbital telemetry data show that the temperature of the main optics is controlled at (16±1) ℃, the temperature of the head circuit box is controlled between 6 ℃ and 8 ℃, while the temperature of the infrared detector heat sink is controlled at (-22±1) ℃: those all meeting the temperature requirements of the scanner. The above indicates that the thermal control scheme is reasonable and effective, which may provide a reference for the thermal control design and optimization of optics payloads of similar types.