This study analyzed associations between a negative change in employment and household income reduction due to the COVID-19 pandemic and subjective well-being (i.e., happiness and life satisfaction). It also examined the mediating role of perceived life control and psychological distress on these associations. The data were gathered from the 2021 Koreans' Happiness Study, a nationally representative cross-sectional survey targeting Koreans aged 15 or older. The total number of respondents was 17,357. Multiple regression analyses showed that a negative change in employment and household income reduction were negatively associated with happiness and life satisfaction. The coefficients of the two independent variables were reduced when perceived life control and psychological distress were hierarchically controlled, suggesting that perceived life control and psychological distress had mediating effects. Bootstrapping confirmed the mediating roles of perceived life control and psychological distress. Those who experienced a negative change in employment and reduced household income tended to show lower perceived life control and higher psychological distress, which, in turn, lowered happiness and life satisfaction. The findings suggest that economic stressors due to the COVID-19 pandemic might lower subjective well-being by decreasing perceived life control and increasing psychological distress. Policy-makers should consider developing an intervention program that promotes perceived life control and decreases psychological distress for individuals with negative economic experiences during the pandemic. Furthermore, governmental support, such as job search, training interventions, and subsidies, should also be considered.