[en] With the DCS of nuclear plant localization process further, requiring the DCS of nuclear plant has better properties. The database is the core part of DCS in LEVEL2. This article describes the database software in the nuclear dedicated instrumentation and control system belonging to CTEC. It has better performance and usability. This article includes the following aspects: (l) The database contains the data dictionary and index table. Database can high-speed read and write through data dictionary. (2) Through point subscribe and caching mechanism, you can speed read data from the database software cycle. (3) Through mapping by point's item, make sure the high speed of the nuclear power plant data acquisition. (4) Users can self-define database point's type and point's item attributes, so the database has very good scalability. (5) The data trigger event is scalable. Finally, this article describes the database software in the practical application of Hongyanhe and Li-ao nuclear power station's KDO/KME system. This article has a very important practical significance for the research and development of domestic database software in the nuclear dedicated instrumentation and control system. (authors)