A charge and discharge management system for managing charging/discharging of a power storage device in a plurality of vehicles having a power storage device and capable of performing external charging for charging the power storage device using electric power from an external power supply and external power supply for supplying power from the power storage device to the outside of the vehicle. A system obtains the scheduled departure times of a plurality of parked vehicles, and determines, among the plurality of vehicles, vehicles whose outside air temperature is lower than the lowest temperature in a predetermined temperature range. To terminate external charging or external power supply at a time closer to a scheduled departure time than a vehicle under environmental conditions.