The Grad-Shafranov equilibrium equation for an anisotropic Tokamak plasma is rederived using the method of Greene, Johnson and Weimer. The stabilizing effect of the anisotropic energetic particle component on the internal kink mode in the Tokamak plasma has been analyzed with the generalized energy principle. Detailed calculation on this effect is performed for two kinds of energetic particle distribution function of slowing down in energy and square top poloidal pressure profile. The stability window of internal kink mode due to the energetic trapped particles with magnetic turning point at high field side is obtained. It's relation with various physical parameters is discussed in some depth.