A power trading management apparatus receives power supply application data including the amount of supplied power and a supply period from a supply-side computer, and receives power demand application data including the amount of requested power and a request period from a demand-side computer, determines whether or not a first trading condition in which the supply period is a period earlier than the request period is satisfied, decides the amount of transmitted power for a power demand apparatus based on an amount of power of the amount of supplied power or the amount of requested power when the first trading condition is satisfied, and stores the amount of supplied power in a power storage and discharge apparatus from a power supply apparatus in the supply period and discharges the amount of transmitted power decided by the decision processing to the power demand apparatus from the power storage and discharge apparatus.