The invention relates to a feed line zero sequence current protection method and device. The method comprises the steps that a power frequency zero sequence current effective value, a power frequency zero sequence voltage effective value and a rated line voltage effective value of the installation location of feed line protection are measured; a zero sequence voltage value is added to correct a zero sequence current measurement value on the basis of maintaining the current setting value in original zero sequence overcurrent protection according to the characteristic that the zero sequence current and the zero sequence voltage of a feed line obviously decrease when a fault is earthed through high resistance, and whether the obtained correction value is greater than the preset feed line zero sequence current protection setting value is judged; and the fault line is cut by operation of feed line protection if the judgment result is yes. The self-adaptive effect for the high-resistance single-phase earth fault can be realized so that the tolerance transition resistance value of the feed line in case of the single-phase transition resistance earth fault can be enhanced.