Abstract: With the background of global warming, Arctic sea ice is rapidly thinning. How to accurately retrieve the thickness of thin ice, particularly ice thickness less than 50 cm, is currently an important research topic. This study addresses the challenge of detecting thin ice thickness in the Arctic using data from the FY-3D microwave imager, a Chinese satellite. Firstly, we analyzed the sensitivity of 15 bright-temperature parameters, including polarization ratio, gradient ratio, and bright-temperature ratio, to thin ice thickness. Subsequently, we developed an Arctic thin ice thickness model adapted to the FY-3D microwave imager by selecting the bright-temperature parameter that is most sensitive to thin ice thickness. Finally, the Arctic thin-ice thickness results retrieved from proposed method in this paper were evaluated by comparison with the Soil Moisture and Ocean Salinity mission (SMOS) Level-3 Arctic thin-ice thickness product. The results demonstrate that both the daily average thickness of Arctic thin ice and the monthly average thickness are in good agreement with the SMOS thin-ice thickness product, with correlation coefficients exceeding 0.8.