Abstract: With the deepening of electricity market reform and the development of community economy, as well as the increasing of grid scale, researching and establishing the adaptability evaluation theory and method of power grid construction not only are realistic demand, but also have great influence on improving the evaluation theory and method of power grid planning. The adaptability evaluation contents for large power grid construction consisted of the adaptability of the national economy, the adaptability of energy structure, the adaptability of grid structure and the adaptability of technology development. This paper also discussed the constructing theory and practice basis of the evaluation contents； put forward eighteen evaluation indexes, such as electricity balance coefficient, capacity-load ratio, etc.； and presented the calculation methods of the indexes.

Key words: large power grid, adaptability, evaluation content, evaluation index