Annual mean temperature plays a very important role to embankment boundary conditions in permafrost regions. On the basis of principle of the boundary layer and unified embankment sizes, governing equation, which involves phase change, and finite element method were applied to study the heat effect along the Qinghai-Tibet Highway. Different locations along the Qinghai-Tibet engineering corridor were chosen to be the studying objects. It is found that annual mean ground temperature increases when annual mean air temperature increases. However, artificial permafrost table decreases remarkably with annual mean air temperature increasing. When the annual mean air temperature is -7.16 ℃, the annual mean ground temperature will be -3.16 ℃ and the artificial permafrost table will be -0.98 m 50 years later; when the annual mean air temperature is -3.21 ℃, the annual mean ground temperature will be -0.1 ℃ and the artificial permafrost table will be -13.11 m 50 years later. Thus, the conclusion can be drawn that stable embankment will turn into unstable one as global climate warming.