This paper presents numerical simulations on frost heave phenomenon observed at the earth structures and pavement structures using a coupled thermo-hydro-mechanical (THM) FE analysis, which can consider the change in deformation-strength characteristics and water retention-permeability characteristics due to freeze-thaw actions, and can reproduce frost-heave of soils under unsaturated conditions based on the results of frost heave tests. In order to evaluate the influences of freeze-thaw action on the interaction between frost-susceptible soil ground and structures quantitatively, a series of numerical simulations for cut slope and pavement structure subjected to freeze-thaw actions were performed. As the results, it was revealed that the coupled FE analysis employed in this study has a sufficient applicability to the precise prediction for the frost-heave behavior of soil ground, and that the frost-heave behavior has a considerable influence on the deformation and failure of earth structures in terms of the deformation and stress state of structures by examining the relation between frost heave and frost penetration depth.