This study proposes a multi-blockchain-based data management framework, focusing on supply chain management system. Our proposed framework introduces a hierarchical blockchain that contains three layers, the public layer, the smart contract layer and the private layer. In the architecture, each company or stakeholder in a supply chain (e.g. warehouse and distribution companies) individually constructs a blockchain in private layer. While private data is managed only in the corresponding private blockchain, a part of the data will be shared to the public blockchain based on the smart contracts defined in the smart contract layer. Using this architecture, users can utilize the integrated data among multiple blockchains by accessing the public blockchain, while protecting privacy in each private blockchain.