With the development of information technology and the unceasingly deepening of archival information construction,the construction of the digital archives in China is currently being developed. But under the heterogeneous system environment and the complex network circumstance,a few problems had not been solved effectively,such as how to protect and ensure the evidential quality of electronic archives in current receiving and prolonged preserving work,and how to safely keep the digital archives. Therefore,during the period of 12th Five-Year Plan,Beijing Archival Bureau has established the Project of Regional Digital Archives which was based on Cloud Computing. And this article starts from the current application status of archives information construction analyzes the existing problems and explores several key technologies of regional digital archives under Cloud Computing in order to solve critical issues mentioned above.