With the maturity of power cable technology and updating of new technology of cable accessories, the failure characteristics of high voltage cable systems and fault causes have changed significantly. In this paper, detailed statistics are carried out for the characteristics and fault cause proportions of 132 failures for 110 kV and above power cable in China Southern Power Grid(CSG)during 2006 and 2016, and 99 failures in the literatures, and the fault characteristics and main reasons of the high voltage cable system in recent years are analyzed. The statistical results show that the present operation reliability of high-voltage cable system in CSG has been improved significantly, while the failure rate has decreased by an order of magnitude compared to 2001. Cable accessories have now already become the weakest part of high-voltage cable systems, the failures of which account for as high as 85.5% without taking external damage into account. For cable, more than 70% of the cable failures are due to external damage, while more than 84% cable accessories failures are due to product quality and improper installation. The statistical result of power cable system can provide a basis for the development of differentiated operation and maintenance strategy.