Base on the evaluation index system of the core competence for the energy enterprise,This paper uses the knowledge of AHM and information entropy to calculate the weight at the first grade index and the second index.Then,it makes an evaluating research on the situation of China's energy enterprise for core competence by the model of unascertained measure.Results show that this model has the characteristics of strong operability and high precision.It is not only favorable to having an objective and correct understanding for China's energy enterprise on their own core competence,but also provides sustained energy security for China's economic development.