A metal air battery system includes an air intake apparatus configured to draw external air, a metal air battery module configured to receive oxygen from the air intake apparatus to perform a discharging reaction, and comprising at least one inlet through configured for oxygen inflow and at least one outlet configured for oxygen outflow, and a flow path connection unit connecting the air intake apparatus to the metal air battery module. A position of the at least one inlet and a position of the at least one outlet is con figured to alternate between a first opening in the metal air battery module and a second opening in the metal air battery module as the metal air battery module is discharged, and the metal air battery system is configured so that at least a portion of the oxygen in the metal air battery module is removed during a charging reaction.