Using the survey data of 21,861 participants from 35 major cities in China in 2018 and 2019, the effect of air quality on participants' mental health was empirically tested based on the ordered probit model. The results showed that smog can significantly influence the mental health of participants. The better the air quality, the better the participants' mental health, while poor air quality results in poor mental health. The older and higher-paid participants demonstrated poorer mental health. Additionally, for different health conditions, the air quality had different effects on the participants' mental health. The healthier the participants, the more sensitive their mental health to changes in air pollution; the poorer the physical condition of the participants, the less sensitive their mental health to changes in air quality. Therefore, we need to more comprehensively and scientifically understand the effect of air quality on health. We need to pay attention not only to the adverse effects of smog on participants' physical health, but also to its effects on participants' mental health to improve both the physical and mental health of participants by improving the air quality.
Keywords: air quality; mental health; ordered probit model.