In recent years, the traceability of product origins is strongly concerned, particularly for food products as they directly influence human health. Therefore, there have been some efforts to develop product origins tracking systems. In this paper, we propose an approach to building a supply chain management system based on the blockchain technology for agriculture product origins tracking. The supply chain model is borrowed from Walmart’s and it is implemented based on the Ethereum framework using the PoA (Proof of Authority) consensus algorithm. Our experiment shows that the proposed system not only fulfills the requirements of a product origins tracking but also takes the advantages of the blockchain technology such as the immutability and security of data, the low cost in making the transactions, and so on.