Cloud storage is the evolution of cloud computing, cloud storage and cloud computing both connections and differences. Cloud storage refers to the use of the network (especially Internet), the use of application software, to provide users with data storage and access functions of a software and hardware combination of data collection system. Cloud storage itself is not a service, it is in order to achieve data storage services provided by a system support. Uncertainty about the location of the cloud servers has led to variable data locations in cloud storage. Data security and privacy security in cloud storage pose a serious challenge to data users. Data security in cloud storage mainly refers to the security of data collection, storage, access, processing and data transaction. Data security in cloud storage is closely related to network security, the legal protection of data security urgently needs to be developed.