As a part of climate system,frozen soil is an important indicative factor of climate change. Freezingthawing processes of frozen soil have the significant effects on the energy-water transfer,vegetation growth and carbon cycle between ground and atmosphere. In this study,the numerical simulation was used to analyze the heat transfer processes accompanied with soil freezing-thawing processes and to intuitively model the transfer processes of energy and water penetration in soil. The cooperative response of velocity and temperature and its effect on the simulation of freezing-thawing process of frozen soil were achieved by coupling the heat conduction model of frozen soil and fluid flow model and by using the finite element analysis software COMSOL Metaphysics. The simulated results displayed intuitively the changes of temperature field and velocity field in the freezing-thawing processes of frozen soil under ideal conditions. On the one hand,temperature field and velocity field were interactive in the freezingthawing processes of frozen soil,and their changes were crucial in the freezing-thawing processes of frozen soil. On the other hand,it was difficult to occur freezing process compared with thawing process. Therefore,it is considered that it is difficult to restore permafrost once its degradation occurs,the environmental change would further be accelerated, and a vicious cycle occurs.