The invention belongs to the technical field of measuring of oxygen concentration using an electrochemical method, and especially relates to a method used for calibrating oxygen concentration using impedance spectrum. The method comprises following steps: an oxygen sensor is introduced into a furnace, and is connected with an electrochemical workstation; the oxygen sensor is heated to a set temperature, and a detection gas with known oxygen concentration is introduced into the furnace; and at last the impedance spectrum is obtained using the electrochemical workstation set at an alternative current impedance spectrum detection mode. Corresponding relationship of the impedance spectrum with the oxygen concentration is established, and a novel oxygen concentration calibrating method is provided.