An electric power management system is a system that performs an exchange of electric power with an electric power system of an electric power company that is a counterparty of the exchange of the electric power, and includes a plurality of the vehicles, each including a battery, and a server that manages an exchange of the electric power between the battery of each of the vehicles and the electric power system. The server manages the exchange of the electric power for each vehicle group in which the vehicles are bundled, and configures the vehicle groups in advance such that distributions of the electric power supply and demand characteristics of the batteries of the vehicles included in the vehicle groups are the same or similar.