Decommissioning of 101 Heavy Water Research Reactor (HWRR) is radioactive and high-risk project which has to consider the effects of radiation and nuclear waste disposal, so the information system covering 101 HWRR decommissioning project must be established to ensure safety of the project. In this study, by col ecting the decommissioning activity data to establish the decommissioning database, and based on the database to develop information management system.