Each time that starting of a vehicle engine is completed, a vehicle control system derives an estimated amount by which the charge in the vehicle battery is less than a predetermined upper limit value of stored charge, and subtracts the estimated amount from the difference between the upper limit value and a lower limit value of stored charge, to obtain an initial allowable discharge amount. An automatic engine stop/restart function is thereafter enabled or inhibited in accordance with whether a net amount of discharge from the battery, since completion of the preceding engine start, exceeds the initial allowable discharge amount.