Since the 11th "five-year plan", China's super-critical technology has been greatly developed, and more and more ultra supercritical units with high parameter have been put into operation formally. The reasonable evaluation on their economic operation efficiency can promote the rational distribution of each unit resource and the improvement of operation efficiency. In accordance with the characteristics of the thermal power unit, as well as the advantages of DEA (data envelopment analysis) method in a multi-input and multi-output model, the evaluation model of ultra supercritical thermal power generating units is established on DEA cross-evaluation model, the evaluation index system of thermal power unit operation is structured simultaneously, and further discussion are expounded with actual examples, which provides a theoretical basis for reference in grasping the actual level of thermal power units and charting the direction of improvement.