Abstract: The energy law is favored due that it does not need to study the complicated stress process during the stope structure failure. Artificial pillar is an important mining field structure in underground mines. Due to the complicated stress and strain in the failure process, we evaluated the stability of the overlying strata by means of the energy conservation. The simplified mechanical model is established through analyzing the mechanical properties and failure mode of the artificial pillar. The equation describing total energy of artificial pillar is derived fromthe energy conservation law. Note that the total energy is has taken account of external load work, gravity potential energy and the strain energy. We also deduced the expression of potential energy function of artificial pillar. Using the catastrophe theory, energy limit-state equation of stability design of artificial pillar is built considering elastic modulus and the ratio of height to width. We discussed and analyzed the external load effect on the stability of artificial pillar. The impact on artificial pillar from external loads was quantitatively evaluated. The practical application of relevant results in the Jiaochong Gold Mine proved the validity of research methods for years. The results of the study show that the established energy limit-state equation of artificial pillar, can provide theoretical guides for the artificial pillar's scientific design and mechanics basis in metal mines.