DEW（Decentralized Exchange of the World）is a global decentralized security exchange, based on smart contracts of Ethereum. It makes a business ecology center that connects the real World with the blockchain. In the role of third party, It integrates supplier and demander, as well as the transaction-supporting service provider which includes the liquidity provider. DEW provides exchange service of digital currencies, stocks, futures, commodities, prediction contracts, and other financial products for token holders. Moreover, the original "Chain-based Hosting Mechanism, CHM" and " Chain-based Clearing Mechanism, CCM" system makes it reality that user’s assets separate from platform operation, that transaction separates from settlement, and that user’s account transaction data is transparent and can be traced back, which ensure the safety of user’s assets.