|Business transaction involves multiple exchanges among business parties. Traditionally, the lack of full trusts among the parties requires an entrusted intermediary to facilitate the exchanges. Blockchain, an innovation to remove a centralized entrusted intermediary,offers many opportunities for business to revolutionize its operations and to conceive new business models. But two issues regarding data storage on blockchain technology have hindered its full-blown deployment. First, business data are sensitive information. Most often, parties not in the transaction are not supposed to see other’s data. However, existing smart contract systems on blockchain are unable to provide data privacy. Second, to uphold integrity and resiliency, blockchain runs a consensus protocol on data that is replicated across many nodes in a network. Data should not be managed by a single service provider; otherwise, it will re-instate a single entrusted intermediary. This proposal addresses data privacy and data storage on blockchain. The Entrusted Decentralized Exchange integrates a private/permissioned blockchain with a peer-to-peer storage network. The permissioned blockchain allows, for transaction that requires privacy, its data can only be read and operated on by parties in the transaction. Other non-transactional data exchange, e.g. business documents exchange, is managed by smart contract, but disembarked on the peer-to-peer storage network. Documents can be encrypted and fragmented. Proxy re-encryption scheme can be applied to allow an encrypted document fragment to be re-encrypted so that the designated receiver can decrypt, while the document fragment is not revealed in the re-encryption process.