Abstract: With the promotion of power system reform, it has become the trend of power market development in our country to allow distributed power supply and other multi-subject agents to participate in the market competition. However, due to the existing power market mechanism is designed according to the centralized power supply mode, the public services, power market trading mechanism and government management system for distributed energy transaction is still more missing. The blockchain technology has the characteristics of decentralization, transparency, fairness, openness and so on. Under the background of the transactive energy system, a decentralized distributed energy transaction mechanism based on blockchain smart contract technology is proposed, which includes auditing, bidding, clearing and settlement. It realizes P2P energy trading among prosumers. And the mechanism is simulated.