This research investigated (1) how the coronavirus pandemic impacted tobacco addiction, (2) which smoker segments were more vulnerable, and (3) how the changes in tobacco consumption were associated with smokers’ satisfaction with physical health and psychological well-being. Data from a large-scale cross-sectional study of adults in China were analyzed. Outcome measures were the quantity of cigarettes consumed per day prior to the COVID-19 pandemic, the quantity after the nationwide outbreak had been contained, satisfaction with physical health, and emotional well-being. Analyses revealed that, after the nationwide outbreak, more individuals quit (vs. started) smoking. Compared to their pre-COVID-19 consumption levels, smokers significantly reduced the quantity of cigarettes they consumed after the nationwide outbreak had been contained. However, there were substantial disparities across individuals: male (vs. female) smokers were less able to curb their smoking; smokers residing in urban (vs. rural) areas or with a longer smoking history were also less able to reduce their smoking. Importantly, a greater reduction in smoking was associated with higher satisfaction with physical health and better emotional well-being. Furthermore, a follow-up investigation revealed that concerns about increased COVID-19 health risks due to smoking were a primary factor driving smokers’ behavior change. Overall, these results suggest that, to help smokers fight tobacco addiction and improve well-being, pandemic health policies need to take account of the differences in vulnerability across individuals and leverage the psychological factors that can facilitate behavior change.