The invention relates to a power system fault pre-alarming method based on the traveling wave electric amount measurement, belonging to the field of power system relay protection; the method comprises: collecting the traveling wave electric amount measured on part or all the power equipment in the power system in real time and synchronously monitoring whether perturbation occurs on the power system; recording the occurrence time of the perturbation; and comparing the characteristics of the traveling waves electric amount on all the power equipment and determining the power equipment where theperturbation occurs; comparing whether the power equipment where the last three times perturbations including the current perturbation occur is the same power equipment; if yes, calculating the interval between the first perturbation and the third perturbation of the last three perturbations; the time interval being smaller than or equal to the preset time interval, judging that the power equipment has a fault and outputting the result of the fault pre-alarming. The invention can promptly provide power system fault pre-alarming information, thus reducing the power system faults, improving thepower system supply reliability and ensuring the safe and stable operation of the power systems.