Abstract: With the developmentof geotechnical engineerings such as underground high-levelnuclear waste disposal, high-voltage electrical powerdistribution, geothermal energy utilization etc., more and moreattentions have been paid on the temperature effects ofunsaturated soils. Temperature effects on basic mechanicalproperties of unsaturated soils are analyzed in terms of both theseepage and strength-deformation. As for temperature effects onseepage characteristics, the effects on the movement of liquidwater and water vapor are studied, and the development of THMmodels is reviewed. As for temperature effects onstrength-deformation characteristic, variation rules of thestrength-deformation versus the temperature are studied bothexperimentally and theoretically, and a summary of the temperatureeffects is given thereby. Finally, some key problems in thecurrent studies are pointed out as well as the development trendsof further studies.