Abstract: This paper briefly described the current situation of reservoirs in the whole country and the Yangtze River Basin, as well as the current situation of reservoir flood control operation and flood limit water level supervision and management. In order to cope with 2020 floods in the Yangtze River Basin, beginning with improving the institutional system, and through the combination of "online" and "offline", the Changjiang Water Resource Commission(CWRC) cooperated with provincial water resources departments had fully explored the potential of the reservoir's flood control benefits on the basis of ensuring the safety of large and medium-sized reservoirs during flood season. On the basis of conscientiously summarizing the effectiveness of reservoir flood control operation and flood limit water level supervision in 2020, we carried out analysis and research on the construction of information platform, implementation of supervision and rectification, and improvement of existing work systems and mechanisms. Based on the research results, we put forward corresponding improvement opinions and suggestions. The research results can provide references for flood control operation of reservoirs in future.