The invention provides a method for predicting electric quantity of a large-scale distribution network based on regional load analysis, and belongs to the field of power grid planning. The predicting method comprises the following steps of: dividing power supply regions; selecting a power supply region; calculating correction coefficient; performing electric quantity prediction on the selected power supply region; and predicting the electric quantity of the distribution network according to the electric quantity prediction result of the selected region. The method is high in precision, quick in calculation, strong in actual operability, simple in principle and good in flexibility; the method greatly reduces the workload of electric quantity prediction data acquisition and analytical calculation of the large-scale distribution network, and can be applied to electric quantity prediction of large-scale distribution networks of all regions in China; and by dividing the power supply regions and analyzing the load of each power supply region, the economic development patterns and the load development characteristics of the power supply regions can be better grasped, and important basis is provided for formulating more focused power grid construction schemes.