INTRODUCTION: Local activities that functioned to prevent frailty in the elderly have been suspended or reduced as a countermeasure against COVID-19. As a result, frailty rates are expected to increase, and frailty is expected to worsen as a secondary problem associated with COVID-19 countermeasures. Therefore, this study aims to determine the extent of frailty in the elderly associated with lifestyle changes implemented as COVID-19 countermeasures, to ascertain actual lifestyle changes and clarify the existence of Corona-Frailty. We will also conduct Corona-Frailty screening to verify the effect of support provided as feedback to supporters of the elderly. METHODS AND ANALYSIS: The survey target area is Takasaki City, Gunma Prefecture, Japan. Phase I aims to verify the short-term effects of COVID-19. A questionnaire will be distributed to 465 community-dwelling elderly people, and responses will be obtained by post. Frailty will be evaluated using the Frailty Screening Index. Respondents who are frail and have had many changes in their lifestyle will be screened as high-risk people, and feedback will be provided to local supporters. The aim of Phase II will be to verify the long-term effects of COVID-19 and the effect of screening. A similar survey will be distributed twice after the first survey, once after 6 months and again after 1 year and the frailty rate will be tested. Furthermore, out of the subjects identified with frailty in Phase I, the progress of those who were screened and those who were not screened will be compared between groups. ETHICS AND DISSEMINATION: This study has been approved by the Research Ethics Committee of the Takasaki University of Health and Welfare (approval number: 2009). The results of this study will be reported to the policymaker, presented at academic conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: UMIN000040335.