Abstract:Firstly the erosion situation of a DC converter contact in UHVDC converter station is introduced，the main causes of contact erosion are analyzed in detail，and it is pointed out that there exists serious hidden dangers to the isolating switches because of inaccurate closing signal，which indicates that such hidden dangers may influence primary equipment and DC control protection system． And then the corresponding solutions are put forward，which have been used for field implementation and have a good transformation effect． So it can provide a reference for other converter stations in China．