The power electronic component in DC distribution network can’t withstand high current, which requires protection remove the fault in a few milliseconds, so the amount of data used for fault location is limited. The existing positioning method based on single ended transient current measurement can’t realize accurate fault position influenced by distributed capacitance, high fault resistance and noise. Considering that the fault has occurred, DC circuit breaker breaks off quickly, in the condition of loss of power system, it is connected in series with a LC injection device to form a decaying oscillation disturbance, and the fault location can be accurately located by using the relationship between the oscillation frequency, the attenuation coefficient and the fault distance. The simulation results show that the proposed method is feasible, with a certain ability to withstand fault resistance, distributed capacitance, noise and line parameter errors. This work is supported by National Key Research and Development Program of China (No. 2018YFB0904104), National Natural Science Foundation of China (No. 51725702 and No. 5177707151407067) and Science and Technology Project of State Grid Zhejiang Electric Power Co. Ltd. (No. 5211JY16000U).