Internet of Vehicles Security - Internet of Vehicles consists of a three-layer architecture of electric vehicles, charging piles, and a grid dispatch management control center. Therefore, V2G presents multi-level, multi-agent and frequent information interaction, which requires a highly secure and lightweight identity authentication method. Based on the characteristics of Internet of Vehicles, this paper designs a multi-subject information interaction and one-way hash chain authentication method, it includes one-way hash chain and key distribution update strategy. The operation experiment of multiple electric vehicles and charging piles shows that the algorithm proposed in this paper can meet the V2G ID authentication requirements of Internet of Vehicles, and has the advantages of lightweight and low consumption. It is of great significance to improve the security protection level of Internet of Vehicles V2G.