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The agricultural product supply chain has the characteristics of long chain, decentralized production, and heterogeneous information from multiple sources, which can easily lead to disconnection and opacity of upstream and downstream information in the supply chain. Traditional traceability data is stored in each node enterprise, and there are problems such as low collaboration trust and poor authenticity in the upstream and downstream data transmission process of the supply chain, which causes consumers to have a trust crisis in the authenticity of traceability information. The blockchain traceability system establishes a distributed database with multi-party participation and joint maintenance, and uses cryptography and consensus mechanisms to establish a trust relationship. It has the advantages of inability to tamper with data and high sharing credibility. In recent years, it has become a research hotspot at home and abroad. The research progress of blockchain traceability systems for agricultural products at home and abroad was systematically summarized, and the blocks were analyzed in detail: blockchain traceability on-chain and off-chain data collaboration, blockchain traceability consensus mechanism, and blockchain traceability data privacy protection. Finally, after the large-scale application of the blockchain, multi-chain and cross-chain technology would become the development trend, and it was predicted that the blockchain technology would be deeply integrated with the new generation of information technology such as the internet of things, artificial intelligence and big data, which was going to promote the blockchain traceability supply chain to enter a new stage of development.