According to some embodiments, an aerosol-generating device includes: an inductive sensor that detects a change in inductance; an induction coil configured to generate a time-varying magnetic field by a current; a susceptor configured to heat an aerosol-generating article inserted into an accommodation space of the aerosol-generating device according to the time-varying magnetic field; a controller configured to: determine whether the aerosol-generating article is inserted into the accommodation space based on the change in inductance detected by the inductive sensor, start heating the susceptor by applying the current to the induction coil based on determining that the aerosol-generating article is inserted into the accommodation space, measure a frequency response of a coupling circuit formed in response to the current being applied to the induction coil, and determine whether to continue to heat the susceptor based on the measured frequency response.