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With the daytoday radiosonde temperature inversion data of 2013 to 2016 in Harbin at 07:00 and 19:00 and the monitoring data of air pollutants of the Harbin environmental monitoring station, the characteristics of the lowtemperature stratification in Harbin and the relationship with the concentrations of four main air pollutants (SO2,NO2,PM10 and PM25) are statistically analyzed The results indicate that the frequency of continuous temperature inversion of the weather was 615% and 588% at 07:00 and 19:00, respectively, in the period of 2013 to 2016 The trends of monthly variation of temperature inversion are basically the same, and the seasonal variation trends are consistent: winter > autumn > spring > summer. The occurrence frequency of the temperature inversion in winter in Harbin is significantly higher than that in summer, autumn and winter. The concentration of air pollutants in Harbin was, in the recent 4 years, positively correlated with the with the frequency and the thickness of the continuous inversion, and positively correlated with the inversion intensity at 07:00, and the correlation with the intensity at 19:00 was not obvious, indicating that the lowlevel atmospheric inversion in Harbin is one of the main factors affecting the air quality of Harbin. The weak cold advection at high latitudes, the warm lower layer, the weak air pressure field at the sea level, and the poor horizontal and the vertical transportation made the pollutants difficult to spread and accumulate, which is the important cause of the severe pollution in the last few days.