Abstract: A bidirectional electric power supplying apparatus comprises a bidirectional charger connected to a smart grid for supplying an electric power to a high-voltage battery of an electric vehicle or supplying the electric power from the high-voltage battery to the smart grid; and a battery management system (“BMS”) controlling a charge of the high-voltage battery and being connected to the bidirectional charger, the BMS controlling the bidirectional charger to supply the electric power from the grid to the high-voltage battery or supply the electric power from the high-voltage battery to the grid. If the mode is set as the smart mode, in consideration of whether the current time is the smart time or the midnight time zone, the electric power is supplied from the high-voltage battery to the grid or supplied from the grid to the high-voltage battery.