Ensuring cloud data integrity has become a security challenge that needs to be solved immediately. Widely-utilized blockchain technology provides a suitable solution to deal with this security challenge. The existing schemes combining blockchain and smart contract technology in which miners perform auditing validation work， suffer from low auditing efficiency， high communication overhead， and heavy auditing burden on Data Owner （DO）. In response to the above issues， a Cloud data Auditing Scheme based on Voting mechanism and Ethereum smart Contracts （CASVEC） was proposed. Firstly， a Decentralized Autonomous Organization （DAO） was designed and deployed on Ethereum by combining voting mechanism and smart contract technology. The nodes of DAO voted to elect an auditing node to replace miners for the auditing verification work， effectively solving the defect of low efficiency in validation audit proof phase. Besides， reputation value was designed to ensure fairness and reliability of the voting process. Secondly， only a few on-chain resources were used to store final auditing results to reduce data volume during communication process， thus effectively solving the problem of high communication overhead in validation audit proof phase. Furthermore， DO only needed to delegate one audit request and retrieve final audit result from DAO. In the above process， DO had no need to call smart contracts so frequently to exchange related information， lightening the auditing burden of DO. Finally， from the theoretical analysis and experimental result perspectives， it was verified that compared with current blockchain-based cloud auditing schemes， CASVEC can significantly reduce time overhead and communication overhead of validation audit proof phase， as well as DO time overhead of audit phase.
