An oxygen enrichment apparatus includes an oxygen enriching unit for generating oxygen-enriched air and a discharge unit for discharging the oxygen-enriched air transferred from the suction unit. The oxygen-enriched air generated by the oxygen enriching unit has an oxygen concentration ranging from about 25% to 35%. The apparatus also includes a suction unit for suctioning the oxygen-enriched air from the oxygen enriching unit and a control unit for controlling the operation of the suction unit. The main body is provided with a display unit for indicating a state that the oxygen-enriched air is being discharged out by the discharge unit. The oxygen enriching unit has at least one oxygen enriching membrane for generating the oxygen-enriched air and a condensed water treating unit is installed at an air passage for guiding the oxygen-enriched air from the oxygen enriching unit to the discharge unit via the suction unit.