The invention provides a current transformer saturation identifying method and device. According to the method, a peak point before a zero crossing point, the zero crossing point and a peak point after crossing point in sampling data are determined, data between the peak point before the zero crossing point and the zero crossing point and data between the peak point after the zero crossing point and the zero crossing point are subjected to normalization processing respectively, then a deviation value through a data sequence obtained after combined data processing, and if the deviation value is larger than zero, it is judged that a current transformer is saturated. Since whether the deviation value is larger than zero or not depends on the overall distribution characteristics of the sampling data, the current signal of the current transformer can be distorted when the current transformer is saturated, and the deviation value obtained by means of the distribution characteristics of the data obtained after the current signal distortion can be larger than zero so that it can be accurately judged that the current transformer is distorted. The method has the advantages of that the capacity of resisting disturbance is high, the method is little affected by noise, the requirement for the sampling frequency is low, the calculation is simple, the requirement for the operational capability of a protective device is low, and on-line real-time monitoring is easily achieved.