question: OBJECTIVE: This study aimed to investigate the different clinical characteristics among elderly coronavirus disease 2019 (COVID-19) patients with and without mental disorders in South Korea and determine if these characteristics have an association with underlying mental disorders causing mortality METHOD: A population-based comparative cohort study was conducted using the national claims database Individuals aged ≥65 years with confirmed COVID-19 between January 1, 2020 and April 10, 2020 were assessed The endpoints for evaluating mortality for all participants were death, 21 days after diagnosis, or April 10, 2020 The risk of mortality associated with mental disorders was estimated using Cox hazards regression RESULTS: We identified 814 elderly COVID-19 patients (255 [31 3%] with mental disorder and 559 [68 7%] with nonmental disorder) Individuals with mental disorders were found more likely to be older, taking antithrombotic agents, and had diabetes, hypertension, chronic obstructive lung disease, and urinary tract infections than those without mental disorders After propensity score stratification, our study included 781 patients in each group (236 [30 2%] with mental disorder and 545 [69 8%] with nonmental disorder) The mental disorder group showed higher mortality rates than the nonmental disorder group (12 7% [30/236] versus 6 8% [37/545]) However, compared to patients without mental disorders, the hazard ratio (HR) for mortality in elderly COVID-19 patients with mental disorders was not statistically significant (HR: 1 57, 95%CI: 0 95-2 56) CONCLUSION: Although the association between mental disorders in elderly individuals and mortality in COVID-19 is unclear, this study suggests that elderly patients with comorbid conditions and those taking psychiatric medications might be at a higher risk of COVID-19