Abstract: In order to solve the problems of data falsification and opaque transportation method in supply chain traceability, combined the characteristics of block chain technology, such as decentralization and data tampering, with supply chain traceability,an improved dynamic practical Byzantine fault tolerance (PBFT) algorithm was proposed. The scoring mechanism was introduced to select the master node to ensure that the network can identify and mark the node with higher score. According to the blockchain infrastructure, the supply chain traceability model architecture was designed as three layers:data layer, contract layer and application layer. In the contract layer the improved dynamic PBFT algorithm was used to update dynamically master node, and the probability that the master node is Byzantine node, and the transaction delay in the network was reduced. The communication cost and transaction delay were used as the measurement indexes to verify the effectiveness of the improved algorithm. The results show that compared with the PBFT algorithm, with the increasing number of nodes, the improved algorithm can significantly reduce the communication cost and transaction delay.