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In recent years, agricultural food safety problems have occurred frequently, which seriously infringe on people's health. Due to the traceability feature of blockchain technology, the agricultural food traceability system based on blockchain was introduced, aiming to better supervise all traceability data generated in the supply chain and ensure food safety. The multi-chain traceability system of agricultural food was established for the whole supply chain. It stored traceability data for multiple participating subjects in blockchain. Due to the difference of traceability demand data of each subject, it was difficult to realize data sharing and access control across supply chain links, it was also difficult to protect sensitive data in a differentiated way, and risk traceability data cannot be subjected to targeted supervision. Therefore, the traceability data for different subjects was not suitable to be stored in the same ledger. Based on this idea, a subject-oriented chain building method was proposed, in which the traceability data for different traceability participating subjects were stored in different blockchains. By analyzing the traceability subjects in the fruit and vegetable supply chain, a multi-chain traceability architecture was established based on the traceability participating subjects. The traceability demand of consumers were realized through the traceability chain, the data flow among enterprises was realized through the sharing chain, the security protection and authorization sharing of the enterprises private data were realized based on the privacy chain, and the regulatory chain was used to realize the management and control of risk data in all links by the regulatory authorities. A subject-oriented multi-chain traceability system was designed and implemented based on Hyperledger Fabric. A suitable storage scheme was designed according to the characteristics of each blockchain. At the same time, in order to ensure the authenticity of the data obtained by each subject after data sharing, a collaborative verification method was proposed to achieve this purpose. The test results showed that the average query time of the traceability chain was 38.86ms, the average time to obtain real shared data was about 806.80ms, the average time to obtain real private data was about 910.35ms, and the average time to obtain real regulatory data was about 675.90ms. The subject-oriented chain building traceability system solved the problems existing in the previous blockchain multi chain system on the basis of realizing the traceability requirements of each subject, and provided reference significance for fruit and vegetable blockchain traceability system.