The invention discloses a fault location method based on traveling wave difference current. The method comprises steps: one-mode voltage uJ1 and one-mode current iJ1 of a DC line starting end J and one-mode voltage uK1 and one-mode current iK1 of a DC line tail end K are acquired; 1-mode wave impedance Zc1 and 1-mode propagation delay tau1 are acquired; one-mode forward traveling wave difference current di<1><+>(t) and one-mode backward traveling wave difference current di<1><->(t) are obtained; forward or backward traveling wave difference current in the one-mode forward traveling wave difference current di<1><+>(t) and the one-mode backward traveling wave difference current di<1><->(t) is used as a reference standard, the traveling wave difference current in the other direction is translated, and the time difference deltat when a Pearson correlation coefficients are maximum of the one-mode forward traveling wave difference current di<1><+>(t) and the one-mode backward traveling wavedifference current di<1><->(t) is acquired, wherein deltat belongs to a range of -tau1 to tau1, the -tau1 is the propagation delay when the fault happens at the starting end J, and the tau1 is the propagation delay when the fault happens at the tail end K; and a fault location is calculated according to the time difference deltat. Thus, the fault location can be reliably judged, which is not influenced by a fault type, and the anti-transition resistance ability is strong.