This paper performs TDR real test for measurement of propagation velocity on #1 Pole of HVDC submarine cable section between Jeju and Haenam, and then measured velocity is compared with theoretical value and velocity provided from manufacturer. The measured velocity is also validated from theoretical process based on CIGRE simplified approach. In this paper, the fault location algorithm using multi-scale correlation of SWT(stationary wavelet transform) and travelling wave is additionally proposed for HVDC submarine cable system, it includes fault signal filter for noise cancellation. Finally, the measured velocity is validated from proposed fault location algorithm test once more.