a new fault line selection method based on the elimination of unbalanced current of zero-sequence active power is proposed by analyzing the principle of active power method and its inaccuracy. The amplitude and phase of real zero-sequence currents can be calculated by the method and the effect of unbalanced current is eliminated. Besides, the difference of active power between fault line and non-fault lines is enlarged. So the accuracy of line selection is improved. The correctness of the method is proved by theory analysis and simulation.