Based on the monitoring data of mountainous rural area, plain rural area and urban area in 2019, the ambient air quality of different regions of Jiyuan city was analyzed. The results show that the average annual concentrations of inhalable particulate matter, fine particulate matter and ozone in the three areas are 91 μg/m3, 55 μg/m3 and 193 μg/m3, respectively, which exceed the standards. The average annual concentrations of SO2, NO2 and CO are 14 μg/m3, 31 μg/m3 and 1.8 μg/m3, respectively, which meet the standards. The comprehensive index of ambient air quality ranked from high to low is urban station, plain rural station and mountainous rural station.