POWER SUPPLY SYSTEM

A power supply system includes a travel mode selection button which acquires a driver request, mode; a management ECU which sets, based on the driver request mode, any among a plurality of travel modes as a setting mode; and an electronic control unit group which controls the flow of electric power in the power circuit under conditions according to the setting mode. The management ECU calculates a sum of a first output upper limit of a first battery B1 and a second output upper limit of a second battery B2 as a total output upper limit Pt_lim, calculates a reference output upper limit Pr_lim which is the first output upper limit of the battery B1 in a reference state, and in the case of the setting mode being a normal mode and the upper limit Pt_lim being smaller than the upper limit Pr_lim, inhibits switching to a sport mode.