An aerosol generating device comprising: a first cartridge configured to accommodate a first material therein and comprising a delivery hole through which an aerosol generated from the first material is delivered; a second cartridge comprising a plurality of chambers for accommodating a second material through which the aerosol delivered from the first cartridge passes and is discharged to an outside of the aerosol generating device, a position of the second cartridge with respect to the first cartridge being changeable so that at least one of the plurality of chambers corresponds to the delivery hole; characterized in that the aerosol generating device further comprising: a remaining amount sensor configured to detect a remaining amount of the first material accommodated in the first cartridge so as to generate a sensing signal; and a controller configured to determine, based on the sensing signal, a consumption amount at which the first material is consumed with respect to a usage chamber that currently passes the aerosol among the plurality of chambers, compare the consumption amount of the first material with a pre-set reference consumption amount of the first material with respect to the usage chamber, and determine a position changing time at which changing of a position of the second cartridge with respect to the first cartridge is required. a first cartridge configured to accommodate a first material therein and comprising a delivery hole through which an aerosol generated from the first material is delivered; a second cartridge comprising a plurality of chambers for accommodating a second material through which the aerosol delivered from the first cartridge passes and is discharged to an outside of the aerosol generating device, a position of the second cartridge with respect to the first cartridge being changeable so that at least one of the plurality of chambers corresponds to the delivery hole; characterized in that the aerosol generating device further comprising: a remaining amount sensor configured to detect a remaining amount of the first material accommodated in the first cartridge so as to generate a sensing signal; and a controller configured to determine, based on the sensing signal, a consumption amount at which the first material is consumed with respect to a usage chamber that currently passes the aerosol among the plurality of chambers, compare the consumption amount of the first material with a pre-set reference consumption amount of the first material with respect to the usage chamber, and determine a position changing time at which changing of a position of the second cartridge with respect to the first cartridge is required. a remaining amount sensor configured to detect a remaining amount of the first material accommodated in the first cartridge so as to generate a sensing signal; and a controller configured to determine, based on the sensing signal, a consumption amount at which the first material is consumed with respect to a usage chamber that currently passes the aerosol among the plurality of chambers, compare the consumption amount of the first material with a pre-set reference consumption amount of the first material with respect to the usage chamber, and determine a position changing time at which changing of a position of the second cartridge with respect to the first cartridge is required.