This guide proposes a practical method for evaluating flood risks for companies, in line with the Recommendations of the Task Force on Climate-related Financial Disclosures (TCFD). It utilizes the latest knowledge and data available for assessing flood risks. The guide is unique because it includes (1) a method that is consistent with a hydraulic engineering perspective, (2) information that practitioners who are unfamiliar with flood risk assessment can manipulate easily, and (3) countermeasures to deal with flood risks.