Blockchain Technology is disrupting in many industries, introducing a decentralized business model over peer-to-peer network. Moreover, many researchers believe that blockchain technology will modernize the global supply chain network, making it more efficient and economical. In order to achieve complex IT solutions like Blockchain with change management for business and IT models, enterprise architecture (EA) is a suitable approach holistically. However, there is a research gap from the blockchain study perspective for the enterprise architecture approach, more deeply inefficient supply chain issues of interoperability, data integration, use of common data, and track and trace issues along with different stakeholders existing in the enterprise domain. Thus, the main goal of this paper is to fill the unexplored research gap academically, more specifically, to solve supply chain issues with Blockchain Enterprise Architecture. As a result of this study, we developed a conceptual new Blockchain Enterprise Architecture (BEA) reference model for the supply chain. We expect our constructed model will be a guide for new business developers, architect designers, and scholars in the supply chain area, and specifically will assist them to trial reference models for new business development in the inception stage. Practically, we demonstrated the BEA reference model for the Pharmaceutical Industry supply chain as a use case.