The propagation of paraxial Gaussian beam in three-dimensional strongly nonlocal media is disccussed with a variational approach. A set of evolution equations are obtained for the beam. The potential function, critical power and ε determined by both the material property and the initial beam width are obtained. The analysis of the potential function shows that the model for the beam propagation in the strongly nonlocal media is valid only when 0≤ε<1/3. A stable optical spatial soliton is found when the input power equals the critical power. Generally, the beam width takes periodical contraction, diffraction, or always diffracts respectively. The results agree with the numerical solutions.