| Summary: | Pollutants emission, meteorological conditions, secondary formation, and pollutants transport are the main reasons for air pollution. A comprehensive air pollution analysis was conducted from the above four aspects in the autumn–winter seasons of 2017–2018 and 2018–2019 at Xingtai, China. In addition, the relationship between PM<sub>2.5</sub> and O<sub>3</sub> was also studied from the aspects of secondary formation and meteorological conditions to find the rules of cooperative management of PM<sub>2.5</sub> and O<sub>3</sub> combined pollution. Taking measures of concentrated and clean heating and controlling biomass burning could make the concentrations of EC, K<sup>+</sup> and SO<sub>4</sub><sup>2−</sup> decrease. The variation trends of PM<sub>2.5</sub> and O<sub>3</sub> concentration in the autumn–winter season of Xingtai were different, and with the increase in secondary formation effects, the concentration of O<sub>3</sub> decreased. Furthermore, the key meteorological conditions that affected O<sub>3</sub> and PM<sub>2.5</sub> formation were temperature and relative humidity, respectively. The relationships of NOR (nitrate oxidation rate) and SOR (sulfate oxidation rate) against temperature presented a “U” shape, suggesting that gas-phase oxidation and gas–solid-phase oxidation were all suppressed at a temperature of around 4 °C. The cities located in the east had more pollutant transporting effects during the pollution processes of Xingtai, and the main transport routes of O<sub>3</sub> and PM<sub>2.5</sub> were not all the same.
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