Despite a rapid increase in male older adults living alone, relatively little is known about their life satisfaction and related factors. Based on Levine’s conservation model, this study aimed to explore predictors of life satisfaction among older men living alone in South Korea. Methods: Using logistic regression, a cross-sectional secondary data analysis was conducted among male older adults living alone (N=548) from the 2020 National Survey of Older Koreans. Results: The factors associated with a risk of lower life satisfaction in older men living alone were income lower than the standard median income, unemployment, living in rural areas, moderate-high nutritional risk, declined sensory function, depression, and social isolation. Conclusion: To enhance the life satisfaction of older men living alone, customized interventions are required, including comprehensive health assessment with a holistic perspective. Addressing economic stability alongside prevention and multidimensional interventions is needed to mitigate nutritional risks, sensory function decline, depression, and social isolation. Healthcare providers and policymakers in local communities should understand the sociocultural characteristics of older Korean men living alone and provide well-suited formal and informal support programs to address these needs.