There is no information in Peru on the prevalence of mental health problems associated with COVID-19 in older adults. In this sense, the aim of the study was to gather evidence on the factor structure, criterion-related validity, and reliability of the Spanish version of the Fear of COVID-19 Scale in this population. The participants were 400 older adults (mean age = 68.04, SD = 6.41), who were administered the Fear of COVID-19 Scale, Revised Mental Health Inventory-5, Patient Health Questionnaire-2 items, and Generalized Anxiety Disorder Scale 2 items. Structural equation models were estimated, specifically confirmatory factor analysis (CFA), bifactor CFA, and structural models with latent variables (SEM). Internal consistency was estimated with composite reliability indexes (CRI) and omega coefficients. A bifactor model with both a general factor underlying all items plus a specific factor underlying items 1, 2, 4, and 5 representing the emotional response to COVID better represents the factor structure of the scale. This structure had adequate fit and good reliability, and additionally fear of COVID had a large effect on mental health. In general, women had more fear than men, having more information on COVID was associated to more fear, while having family or friends affected by COVID did not related to fear of the virus. The Spanish version of the Fear of COVID-19 Scale presents evidence of validity and reliability to assess fear of COVID-19 in the Peruvian older adult population. Keywords Older adults . Reliability . Fear of COVID-19 . Bifactor model . Validity COVID-19, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2), has spread rapidly throughout the world (Huang and Zhao 2020), affecting 188 countries with 13,135,616 confirmed cases and 573,869 of deaths, and increasing (data obtained from https:// coronavirus.jhu.edu/map.html, on July 17, 2020). This disease presents a higher risk of mortality in people with comorbidity and older adults (Morley and Vellas 2020). In Latin