<p>This longitudinal study examines the paradox of aging and its influence on life satisfaction among older adults in South Korea, a nation undergoing rapid population aging. Using data from the Korean Longitudinal Study of Aging (KLoSA) across eight waves (2006–2020), this research analyzes the effects of demographic, economic, health and social factors on life satisfaction among 33,701 individuals aged 65 and older. The findings reveal that, despite declines in physical and cognitive health, life satisfaction tends to increase with age, reinforcing the aging paradox. Significant differences in influencing factors between genders were observed, with education level and religious affiliation playing key roles for women, while household assets uniquely affected men. The study underscores the necessity for comprehensive policies addressing the diverse needs of the elderly population to enhance well-being in later life. </p>