There is a need to consider people's welfare when for-mulating policies, where subjective well-being is a proxy for welfare. Although it is important to elucidate the mech-anisms underlying the decline in subjective well-being associated with flood experience when making policy, this has not been studied in detail. Therefore, this study sought to clarify the relationship between flood experience and subjective well-being, focusing on anxiety about floods. We conducted an online questionnaire in Tochigi Prefecture, Japan and analyzed the results of 2,630 respondents. Medi-ation analysis revealed that flood experience does not have a direct effect on subjective well-being (p < 0.05) but exerts a negative effect through anxiety about floods. The same was true when only people with recent flood experience were analyzed. This study suggests methods for restoring subjective well-being to its original level after a flood, such as managing anxiety about floods.