The electricity demand is closely related to the economic development. At different stages of economic and social development，the relationships between the electric power and the economy change accordingly. Taking the main factors affecting the power-economy relationship （such as industrial structure，energy intensity，policy，climate，etc.）as the starting point，this paper comprehensively analyzed the long and short-term power and economic relations of the whole province and sub region from the total amount correlation，growth relevance，structural relevance and energy intensity，etc. Finally this paper evaluated and predicted the electricity demand situation of the “13th Five-Year” period in Henan Province according to the evolution of power economic relations and different economic development scenes.