Abstract: In order to understand the effects of urbanization on the Earth's ecosystem, the impervious surface coverage(ISC) has been recognized as a geographical indicator to reflect the intensity of human development activities with rapid urbanization.The PM_2.5 pollution is used to indicate air quality.The relationship between ISC and PM_2.5 pollution was explored with two levels based on spatial statistics.From 2000 to 2015, the ISC in Kunming increased from 9.36% to 16.37%, while the PM_2.5 concentration increased from 17.12 μg/m³ to 28.63 μg/m³.The spatial distribution of the PM_2.5 aggravation was consistent with the impervious surface expansion in Kunming.The growth of ISC in the southeast(11.56 to 25.78%) was greater than that in the northwest(2.12 to 5.15%), and the increase of PM_2.5 concentration in the southeast(21.37 to 36.75 μg/m³) was also greater than that in the northwest(4.56 to 10.65 μg/m³).The relationship between ISC and PM_2.5 concentrations was explored at the town level and the station level.The impervious surface and the PM_2.5 pollution in Kunming both had significant spatial autocorrelation between the towns with Moran's Index of 0.29 and 0.58(P < 0.001), respectively.For towns' ISC greater than 5%:58.14%(25/43) of the towns were degraded; for ISC > 10%:71.43%(25/35) of the towns were degraded; for ISC > 25%:100%(26/26) of the towns were degraded.In contrast, for towns with ISC < 5%:none of the towns were degraded.With the least square method, the results showed a good fitting(R²=0.803, P < 0.001) between the towns' ISC and PM_2.5 concentrations.Moreover, at the station level, the relationship between ISC of the stations' buffer(2000 m) and PM_2.5 concentrations were explored(R²=0.893, P < 0.001) with Pearson's Correlation, indicating ISC has strong association with PM_2.5 concentration.Thus, the proportion and spatial distribution of impervious surface should be considered in National New-Type Urbanization Development, making cities surrounded by enough green belt and water areas.