With China entering the era of big data, the storage and management of big data has become a hot issue. The proposal and use of distributed storage technology has achieved good results. The continuous development of Internet communication technology and the popularization of computer information technology promote the evolution of traditional data model. The distributed storage system for big data has strong expansibility. It can optimize the existing storage space, realize the optimal allocation of space resources, and reduce the cost of data storage. Cloud computing as a resource sharing business computing model, it receives a huge amount of data every day, and the amount of data is still expanding. This has caused great pressure on distributed storage in cloud computing environment. This paper studies the distributed storage technology of database big data based on cloud computing, in order to strengthen the data management in the era of big data and improve the security and utilization of data.