An air filtering apparatus in which electrolytic water generated by an electrolytic unit is supplied to a gas-liquid contact member to infiltrate the electrolytic water into the gas-liquid contact member and reflows to a water receiving tray, air is fed to the gas-liquid contact member by an air blowing fan to bring the electrolytic water into contact with the air in the gas-liquid contact member to filter the air is equipped with a brine supply unit for supplying brine to the water receiving tray, and a controller for setting a water exchange operation mode in which water stocked in the water receiving tray is discharged and new water is supplied into the water receiving tray, and operating the brine supply unit when the water exchange operation mode is selected and supplying brine into the water receiving tray.
