Abstract: Based on the real-time observation data from the 33 meteorological stations in Heilongjiang province from 2008 to 2018, and the national standard i.e."Grades of Atmospheric Self-purification Capability", the spatial and temporal variation characteristics of atmospheric self-purification capability (ASPC) were analyzed and the relationship between ASPC and air quality index (AQI) in Harbin was investigated.The results show that the average ASPC index is 12.6×10⁴ km·a^-1 from 2008 to 2018 with an increasing trend in Heilongjiang province.Since 2015, the ASPC has increased significantly.The ASPC is highest in spring, fewer in autumn, and lowest in winter.In terms of spatial distribution, the ASPC is low in the north and high in the south and includes two levels i.e.the second level and the third level.Specifically, the ASPC in the whole province is in the second level in spring, which is favorable to the removal of atmospheric pollutants, while that in Mehe is in the fifth grade in winter, which is unfavorable to the removal of pollutants.There is a significant negative correlation between AQI and ASPC index in winter in Harbin.Considering the ventilation and rain washing effect, the ASPC has a close relationship with the AQI and directly affects the air quality in Harbin.