An induction-heating cooking system, comprising: - a plurality of heating coils closely arranged for heating a single heated-subject in cooperation with one another; - a plurality of drive circuitries, each one of the drive circuitries supplying a high-frequency current of the same frequency individually to one of the heating coils; characterized by further comprising: - a plurality of n-th order component extractors, with n being a natural number, each one of the n-th order component extractors extracting an n-th order drive current component of the drive current through each of the heating coils and an n-th order drive voltage component of the drive voltage across each of the heating coils; and - a controller calculating a load resistance and a resonance frequency of each one of the heating coils based upon the n-th order drive current component and the n-th order drive voltage component extracted by the corresponding n-th order component extractors; wherein the controller is adapted to: a) determine whether or not the heated-subject stands over each one of the heating coils in accordance with the calculated the load resistance ( R i) and the calculated resonance frequency ( Fr i) of each one of the heating coils when controlling each of the drive circuitries to supply the high-frequency current having a first detection frequency ( F S1), b) define a drive frequency ( F D) as the highest one of the calculated resonance frequency ( Fr i) of the heating coils plus a predetermined additive frequency (Δ F), and c) control each of the drive circuitries of the heating coils which the heated-subject is determined as standing over, to supply the high-frequency current having the drive frequency ( F D). - a plurality of heating coils closely arranged for heating a single heated-subject in cooperation with one another; - a plurality of drive circuitries, each one of the drive circuitries supplying a high-frequency current of the same frequency individually to one of the heating coils; - a plurality of n-th order component extractors, with n being a natural number, each one of the n-th order component extractors extracting an n-th order drive current component of the drive current through each of the heating coils and an n-th order drive voltage component of the drive voltage across each of the heating coils; and - a controller calculating a load resistance and a resonance frequency of each one of the heating coils based upon the n-th order drive current component and the n-th order drive voltage component extracted by the corresponding n-th order component extractors; a) determine whether or not the heated-subject stands over each one of the heating coils in accordance with the calculated the load resistance ( R i) and the calculated resonance frequency ( Fr i) of each one of the heating coils when controlling each of the drive circuitries to supply the high-frequency current having a first detection frequency ( F S1), b) define a drive frequency ( F D) as the highest one of the calculated resonance frequency ( Fr i) of the heating coils plus a predetermined additive frequency (Δ F), and c) control each of the drive circuitries of the heating coils which the heated-subject is determined as standing over, to supply the high-frequency current having the drive frequency ( F D).