Abstract: Individual fixed effect panel models were used to analyze the socio-economic influencing factors of the air quality of seven counties in Nantong City from 2011 to 2020. The results of the panel regression models were compared under different industrial developmental levels. The results showed that the influencing factors of air quality have obvious differences among different levels of industrial development. When the level of industrial development was low, industrial smoke and dust emissions had a significant negative effect on air quality, as same as the growth rate of per capita GDP. When the level of industrial development was high, the comprehensive energy consumption had a negative impact on the air quality, while the proportion of the secondary industry and the growth rate of the per capita GDP had a positive impact on the air quality. These models would provide more accurate prevention and control directions for the air pollution prevention in Nantong during the 14th Five-Year Plan period.