Abstract: Based on monitoring data of main pollutant (PM₁₀,PM_2.5,SO₂,and NO₂) concentrations and meteorological data from urban and suburban areas in Nanjing during the Spring Festival of 2014 and 2015,the effects of fireworks forbidden on air quality were analyzed.The results indicate that fireworks forbidden during the Spring Festival of 2015 result in improving air quality effectively in Nanjing.Air quality index (AQI) decreases 20%-30% during the Spring Festival of 2015,comparing to that during the same period in 2014.Air quality remains in a good level from New Year's Eve to January 3,2015 according to the lunar calendar.During the Spring Festival of 2015,SO₂ and NO₂ concentrations vary relatively small and reach the secondary level according to Chinese air quality standard.However,PM₁₀ and PM_2.5 concentrations show an opposite variation with those in 2014 and have relatively larger range of variation,varying from 13 μg·m^-3 to 234.5 μg·m^-3 and from 17.5 μg·m^-3 to 320.4 μg·m^-3,respectively.The main pollutants that cause air pollution during the Spring Festival in Nanjing are primarily PM_2.5,and then PM₁₀.The maximum hourly mean concentrations of PM₁₀ and PM_2.5 during the Spring Festival of 2015 only take up 51% and 40% to that of 2014,respectively.In addition,PM_2.5 concentrations in urban and suburban areas reduce obviously in the Spring Festival of 2015,but the difference between the two areas is small.Meteorological factors greatly influence pollutant diffusion during the Spring Festival in Nanjing;however,the fireworks prohibition has a dominant effect on the reduction of PM_2.5 concentration.