With the increasing demand for energy in China

the construction of ultra-high voltage direct current（UH-VDC）transmission and long-distance pipeline is carried out on a large scale. When the DC grounding electrode oper-ates in monopolar mode

there will be some part of the current flowing into the buried metal pipeline

which will leadto the electrochemical corrosion of the metal pipe

speeding up the breakage of the pipe. The purpose of this paper isto systematically introduce the research on corrosion of metal pipes by the earthing current of UHVDC groundingelectrode

which includes the mechanism and influencing factors of accelerated corrosion of pipeline under DCground current

detection and evaluation of stray current in ground as well as typical measures of pipeline corrosionprotection in practical project. Contrasting the solution of pipeline corrosion caused by the electrified rail

the pipe-line corrosion caused by the grounding electrode of UHVDC is analyzed. Finally

the prospect of the research direc-tion is given

and the solution to the key problems is put forward.