Background: Several studies have been conducted on the effects of floods on the health of the affected community. We aimed to determine the effects of floods as the most common disaster on hypertension (HTN) as one of the most common noncommunicable diseases (NCDs). Materials and Methods: Four databases including Medline, Scopus, Google Scholar, and ScienceDirect were searched with the search strategy protocol up to the end of June 2021 and with the keywords of flood and high blood pressure or hypertension. Grey literature database and websites of WHO, UNDRR, and PreventionWeb were also searched. After removing duplicate articles, abstracts of the relevant titles were reviewed, and eligible articles were included for full-text review. Finally, the study variables were extracted from selected articles. Results: The search strategy resulted in eight final relevant articles from 48, 980 articles. All final articles noted meaningful effect of flood on high blood pressure. There was a positive correlation between anxiety level, property loss, financial loss, physical activity, use of alcoholic beverages, interruption of medication, and medical cares with HTN. Different studies have also reported long-term effects of flooding on blood pressure. Conclusions: The flood has significant effect on high blood pressure in affected population. However, cases of unknown HTN in the affected population should also be considered, so screening is recommended in the affected community.