The electric power supply and demand control device judges whether or not electric power shortage is occurred or whether or not electric power surplus is occurred in the electric power supplier and demander provided with the electric power supply and demand control device based on data on total electric energy, the amount of maximum electric power demanded, and the amount of total electric power demanded of the following day in each electric power supplier and demander, predicted by a neural network; receives electric power from other electric power suppliers and demanders provided with the power generation devices and/or the electrical storage devices in the case where electric power shortage is occurred in the electric power supplier and demander; and controls to deliver electric power to other electric power suppliers and demanders in the case where electric power surplus is occurred in the electric power supplier and demander.