An aerosol generating device includes a housing including a first surface, a second surface opposite to the first surface, a side surface between the first surface and the second surface, and a mouthpiece formed on the first surface, an oscillator accommodated in the housing and configured to generate a microwave with a preset frequency, a resonator accommodated in the housing and configured to resonate the microwave to generate an amplified electromagnetic field, and a cartridge including an aerosol generating material and being insertable into the housing, wherein an aerosol may be generated as at least a portion of the electromagnetic field heats the aerosol generating material, the housing may be provided with a cartridge insertion hole through which the cartridge is inserted, and the cartridge insertion hole and the mouthpiece may not overlap.