The sustainable growth competence of an enterprise is unique, important and quite difficult to identify. This competence can be built through integrating the internal and external factors. The increase of the sustainable growth competence comes from the mutual restriction and interaction among the four elements like the sustainable growth level, the efficiency, the potential and the degree of harmony. Through systematic evaluation of the competence, we can clarify the key elements and possible problems for the enterprises to achieve sustainable growth, which could also provide the scientific basis for the enterprise to set up the pre-alarming system and implement the long-term sustainable growth strategy. The grey entropy is quite applicable in exploring the theory and methodology of the sustainable growth evaluation because it can reflect the structural feature and changing trend of the system evolution.