There are problems of incomplete function, just a single detection scheme and difficult control and management with the existing V2G DC charging pile field detection device. Thus a detection scheme and system for a V2G DC charging pile are designed in line with relevant national standards. First, given the needs, three detection schemes, i.e. field, laboratory and power battery schemes, are designed. Different detection schemes correspond to different environments and items of V2G charging piles. Then, for the three detection schemes, the hardware and software of the detection system are designed. These can detect the charging and discharging function, DC output and grid-connected performance and protection function of the pile. The detection system can also evaluate the state of the power battery of the electric vehicle, and in this way judge the potential risk to the battery. Finally, by testing the V2G DC charging pile and vehicle power battery in different circumstances, the results show that the designed scheme and system can accurately detect the function and performance of a V2G DC charging pile.