Abstract: With the increasing inter-industry correlation, flooding not only causes direct losses, but also leads to more severe indirect economic losses. In order to comprehensively assess the impact of floods on the economic system, taking Hunan Province as a case study, we constructed an input-output (IO) model to measure the indirect economic losses associated with various industries under different inundation depths in the static scenario and screened out the industries that were more sensitive to the impacts of floods; and then with the help of a dynamic inoperability input-output (DIIO) model, we assessed the total output economic losses caused by floods in the dynamic scenario and compared the difference between the two total output economic losses. The results of the study show that:①in the static scenario, with the increase of inundation depth, the direct and indirect economic loss of each industry after the disaster rises, and the economic loss of highly sensitive industries grows much faster than that of other industries, and its total indirect economic loss accounts for as much as 66.83% of the total indirect loss;②in the dynamic scenario, the indirect economic loss of the affected industries is more sensitive to the changes of the recovery period, and the recovery period can be reduced from 12 months to 1～6 months, and the total output economic loss will be significantly reduced due to changes in indirect economic loss. This study will improve the efficiency of flood prevention and emergency management, reduce the comprehensive economic loss of flood disasters, and enhance the resilience of regional economy.