An induction heating cooker having an oil temperature control function by of the amount of change of an operating frequency, and a control method thereof, the induction heating cooker including a heating coil, an inverter unit, a driving unit, a detection unit to detect a value of a current that flows at the heating coil, and a control unit to calculate an operating frequency of the driving unit according to the value of the current, to vary the operating frequency so that the heating coil maintains a constant output that corresponds to an output level, and to determine whether oil accommodated in a container placed on the heating coil is overheated, by use of an amount of change of the operating frequency, and the maintenance or the control of the temperature of oil may be achieved.