This article examines the heterogeneity of the association between obesity and COVID-19 mortality across various dimensions, including COVID-19 vaccination rates, mask mandates, gathering restrictions, and household income. Using multivariate regression analysis on U.S. county-level data over 2020-2021, the authors found that county-level adult obesity rates were positively associated with COVID-19 death rates. The results suggest that on average, a 10-percentage-point decrease in adult obesity rate is associated with a decrease in COVID-19 deaths by 4.79%-5.98% in the U.S. Considering that the average adult obesity rate in the U.S. is higher than the global average, this finding may explain why deaths due to COVID-19 were disproportionately large in the U.S. In addition, the authors found that association between obesity and the COVID-19 death rate is much more pronounced in groups with low vaccination rates, weak mask mandates, loose gathering restrictions, or low household incomes, indicating the importance of COVID-19 response policies and income to people with obesity facing a pandemic. The study results contribute to policy discussions surrounding preparation for COVID-19-like pandemics. Food policies and health promotion strategies that encourage physical well-being to reduce obesity prevalence may help reduce mortality in future pandemics.