Provided is an aerosol generation device including: a power supplier comprising a first battery and a second battery; a controller; and a heater, wherein the controller is configured to control the power supplier to operate according to one of a first mode in which power is supplied to the heater by using the first battery and a second mode in which power is supplied to the heater by using the second battery, and control the power supplier to supply greater power in the first mode than in the second mode.