Abstract: In this paper,the propagation process of the pulse signal on HVDC grounding pole line and the selection of the pulse signal are analyzed to avoid the blind zone of single pulse affecting the fault location. A fault location method for HVDC grounding pole line using multi-pulse injection method is presented according to the single-end distance measurement principle of the pulse injection method. This method is to detect the running states of the grounding electrode lines by the plus of8μs periodically. When the line fault is determined,the fault location is detected by the plus of 4μs or 2μs. Finally,the fault location result is obtained in the form of the average value. The PSCAD/EMTDC simulation results show that this method can locate faults both in bipolar and unipolar operation of the DC system,and can meet the engineering requirements for error accuracy,avoid the influence of transition resistance,reduce the large range of ranging blind area caused by wide pulse selection, and improve line ranging while ensuring high recognition of the reflected pulse.