Abstract: Based on the air atuo-monitoring data from 2016 to 2021,the target area was divided in to three regions,namely,Chengdu Plain（CP）、Northeast Sichuan（NS） and South Sichuan（SS） according to the geographical location of cities in Sichuan Basin.The spatial-temporal variation characteristics of air quality in this research area were analyzed.The results showed that the air pollution prevention and control work in Sichuan Basin were effective.Its air quality had a big promotion.The concentration of SO₂、CO、PM₁₀ and PM_2.5 decrease significantly（p<0.05）,but the concentration of O₃ increases slowly.The spatial distribution of air quality and air pollution characteristics had obvious differences among three regions in this research.The spatial distribution of pollutant concentration was high in the West and South of Sichuan,but low in the East and North of Sichuan.The primary pollutant at the CP、NS and SS were O₃、PM_2.5 and PM₁₀ respectively.The impact degree of three regions on the air quality of Sichuan basin was CP>SS>NS;The CP and SS were the key areas of air pollution control in the later period.