Abstract:Cloud computing is popular because of its large storage capacity and computing power. However, cloud technology brings new threats to data security. Due to the large amount of data exchanged between the cloud platform and users, there is a series of security risks in the whole life cycle of the data. According to these data security risks, this paper studies from four aspects: state regulation, technical research and development of professionals, credible services of cloud providers and prevention awareness of cloud-related personnel, and puts forward corresponding data security protection models and defense strategies. It can solve the problem of cloud computing data security risk better.