Abstract: In order to study the thaw subsidence properties of cementimproved soil, experimental research were carried out with two typical soils in Nanjing region, clay and sand mixed with the cement. The experiments show that the law that mixing ratio of cements has impact on the thaw subsidence is similar to the law on the frost heave, and the thaw subsidence coefficient of clay or sand cementimproved soil declines exponentially with mixing ratio of cement increasing. The optimal mixing ratio to of clay and sand in Nanjing region are 10% and 5%. The thaw subsidence coefficients are only 16.4% and 18.5% when the mixing ratio is the optimal mixing ratio. The melting temperature has no impact on coefficient of thaw subsidence, but observably impact on time of thaw subsidence. After clay cementimproved soil was frozen, the coefficient of compression increased by 31.1%-68.4% while the coefficient of compression of sand cementimproved soil was invariant. By comprehensive analysis, mixing the cement into soil can control thaw subsidence. The force thawing doesn′t increase the magnitude of thaw subsidence but can reduce by a large margin the time of thawing.