Aiming to address the issue of rice supply chains susceptibility to private data leakage in data sharing during the use of block chain technology for traceability，the block chain technologys distributed shared global ledger and nontampering features were utilized, the block chainbased modeling and system implementation of rice supply chain traceability information protection was studied. Firstly, the supply chain traceability privacy data was symmetrically encrypted by using the ciper block chaining (CBC) model before it was uploaded to the block chain network, while the key was encrypted by using elliptic curve cryptography (ECC) and written to the block chain network, the block chain network stored the encrypted ciphertext of the privacy data and authorized the node to view the block chain traceable privacy data using its own private key to achieve the sharing of privacy data in the block chain network. On this basis, the security performance of the method was analyzed and the cipher diffusion of the encryption algorithm reached 0838. Finally, the whole supply chain information traceability system of rice was designed and implemented based on the Hyperledger Fabric platform, and validated and analyzed through specific application cases. The results showed that the nodal authorization method proposed differentiated between nodes for the privacy data that needed to be protected, striking a balance between the need for encryption protection of privacy data and the need for public regulation of supply chain traceability data, the problem of data sharing between multiple nodes of rice supply chain production, processing and circulation was solved, which provided reference for the research on the traceability of rice supply chain.