The features of block chain technology, including decentralization, distributed storage, open, transparent, consensus mechanism, security, information encryption and anonymity, which provides an important way to improve the value of modern agricultural products supply chain. Through analyzing the concepts and connotations of agricultural products, logistics, agricultural products logistics, supply chain and agricultural product supply chain, this paper further defines the supply chain of agricultural products and its business logic. The problems existing in the circulation of agricultural products were analyzed and pointed out. With the demand of agricultural product supply chain, this paper analyzes the concept, technical characteristics and structure of block chain technology, and put forward the logic structure of agricultural product supply chain based on block chain. Furthermore, the information flow and capital flow in the processed architecture were discussed. This study provides useful inspiration and reference for the study of supply chain of agricultural products based on block chain.