The traveling wave protection of HVDC transmission line is easily affected by fault resistance and requires high sampling rate of the device. While in order to prevent misuse caused by the line distributed capacitance, operation speed of the current differential protection which serves as a back-up protection is usually slow, losing the characteristic of fast speed. By the difference of the polarities of the fault components of voltage and current detected, this paper proposes a directional pilot protection method of fault component for HVDC transmission lines based on Hilbert-Huang transform. On the basis of analyzing the difference of the polarities of the fault components of voltage and current for different faults, the polarities of the fault components can be calculated by Hilbert-Huang transform to distinguish different fault directions. Based on PSCAD/EMTDC, a simulation model is built and the simulation results show that the proposed method can effectively identify the various faults with high speed, sensitivity and reliability and is less affected by the transition resistance. This work is supported by Smart Grid Technology and Equipment Special Subsidy Program of National Research Program of China (No. 2016YFB0900604).