Soil Freeze-Thaw processes and parameters play an essential role in land surface processes, climate models, global change and other critical aspects. Since passive microwave is sensitive to soil moisture, and has a high revisit frequency, it is suitable for the monitoring of soil Freeze-Thaw processes. Research achievements in microwave remote sensing of frozen soil are reviewed and discussed in this paper. According to the research demands including frozen soil radiation simulation and globally monitoring of frozen soil, several current scientific issues are  proposed and analyzed. The ability of microwave remote sensing of Freeze-Thaw processes over complex landscapes involving soils, snow cover and vegetation cover is well evaluated. A preliminary research proposal  is presented for addressing these issues.