The current retrospective study aimed to investigate the association between organizational factors and nursing staff in geriatric hospitals and coronavirus disease 2019 (COVID-19) incidences and deaths using secondary data from governments nationwide in Korea. We used data on the number of COVID-19-confirmed cases and deaths among older adults in geriatric hospitals and nursing staff levels in those hospitals. We found that when the RN level was higher than the sample mean, the number of COVID-19-confirmed cases by geriatric hospital was significantly lower (4.3%; p = 0.05) and the number of deaths by geriatric hospital was marginally significantly lower (1.4%; p = 0.05). This study presented the national description of geriatric hospitals during the COVID-19 pandemic in terms of organizational and nursing staff factors. Findings highlight the impact of nursing staff skill mix and number of geriatric hospitals during the COVID-19 pandemic in Korea. It is necessary to allocate a realistic designation of infection control staff and establish a clear standard so infection control activities in geriatric hospitals can proceed systematically. [Research in Gerontological Nursing, 16(6), 302-311.].