The invention relates to a current transformer saturation identification method comprising the following steps: acquiring three-phase current data needed for current differential protection and preprocessing the data; setting a current transformer saturation identification plane and partitioning the current transformer saturation identification plane; identifying whether a current transformer is saturated or not according to the data and the saturation identification plane; and reopening the fault in the saturated period of the current transformer according to the saturation recognition judgment and the fault opening criterion. By adopting the technical scheme, the action performance of current differential protection is enhanced.