Abstract: 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 that enable miners to perform auditing validation work, which combines blockchain and smart contract technology, have three defects as low auditing efficiency, high communication overhead, and heavy auditing burden on Data Owner (DO). Therefore, a cloud data auditing scheme based on voting and Ethereum smart contracts was proposed, which called CASVEC. Firstly, a Decentralized Autonomous Organization (DAO) was designed and deployed on Ethereum by combining voting mechanism and smart contract technology. Nodes of DAO were responsible for voting to elect an auditing node to replace the auditing verification work of miners, so as to effectively solving defect of low efficiency in validation audit proof phase. Besides, the voting mechanism designed reputation value to ensure fairness and reliability of voting process. Secondly, only a few on-chain resources were used to store final auditing results in order 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 retrieved 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 the blockchain-based cloud auditing schemes，CASVEC can significantly reduce time overhead of validation audit proof phase, communication overhead of validation audit proof phase, and time overhead of audit phase DO.