Abstract: Objective To explore effects of atmospheric nitrogen dioxide （NO₂） pollution on mortality in cities of Guangzhou, Foshan and Zhuhai in Guangdong Province. Methods Air pollutant data, meteorological data and the daily case of death in the three cities were collected from 2013 to 2016. Basic characteristics of the data were statistically described and the correlation was analyzed by Spearman. Then, generalized additive model （GAM） was used to explore the relationship between the daily average concentration of NO₂ and daily mortality in the three cities. Results The average daily concentrations of NO₂ in Guangzhou, Foshan and Zhuhai from 2013 to 2016 were 46.4, 48.4 and 33.1 μg/m³, respectively, meeting the National Standards at Level 2（80 μg/m³）. The daily average concentration of NO₂ in the atmosphere of Guangzhou had a statistically significant effect on the daily total number of deaths and the number of deaths from circulatory diseases at the same day, lag1 and lag2 days （P<0.05 for all）. There was a statistically significant effect of the daily average concentration of NO₂ in Foshan City at lag1 and lag2 days on the daily total number of deaths of residents and the daily number of deaths from circulatory diseases （both P<0.05）. Both Guangzhou and Foshan showed the greatest effect on lag1 day. The daily average concentration of NO₂ had an impact on the daily death toll of respiratory diseases of residents in Guangzhou （ER=1.38） on lag2 day. Conclusions The incrase in the concentratienof The increase in the cocentration of NO₂ air pollutantion can affect the risk of daily mortality of residents.

Key words: Air pollution, Nitrogen dioxide, Death, Generalized additive model