Abstract:[Objective] To explore the dynamic changes of soil hydrothermal and salt in seasonal freezing and thawing period and its mechanism in order to provide some theoretical basis for soil salinization protection and administer in arid and semi arid areas.[Methods] Horqin meadowland was taken as a research area. Where the hydrothermal and salt observation data of meadow in the Aruga Eco-hydrological Experimental Station of Horqin left-wing post in November 2013-2014, were simulated and analyzed by SHAW model.[Results] The simulated results of soil heat and salt were better, and the root mean square error (RMSE) was 0.02~0.07. Due to the influence of meadow groundwater level, the model has a large deviation from the simulation results of water content, but its standard deviation and mean deviation are within allowable range.[Conclusion] The SHAW model can be used as the optimal model for the simulation of the study. It can compensate for the shortage of artificial observation data intermittent or missing, and can quantitatively predict the migration of hydrothermal salt in the vertical one-dimensional permafrost and free permafrost system under natural conditions.