Urban air pollution is an important issue facing China in the midst of rapid urbanization and economic development. To investigate the regional air quality characteristics and its drivers in Northeast China, this paper compares the spatial and temporal characteristics of air quality between cities and analyzes the influence of socioeconomic variables by using statistical analysis methods and geographic model. The results show that the air quality index (AQI) showed a downward trend in time and decreased from southwest to northeast in space. The duration of heavy pollution condition was not only controlled by the distribution of pollutant concentrations, but also influenced by the topography. Based on the mean concentrations of the 6 pollutants, 37 cities were divided into 4 categories by cluster analysis, reflecting the levels and characteristics of pollution. The level of industrialization was the most important cause for air quality, followed by the size of the city and the degree of economic development. The AQI predicted by geographic weighted regression model (GWR) showed a lower goodness of fit in developed cities, indicating that the factors controlling air quality are more complex in these regions. The influence of different socioeconomic metrics on AQI showed large spatial differences. AQI was more sensitive to variations in socioeconomic metrics in less developed small and medium-sized cities. This study provides a theoretical basis for revealing the causes of urban air pollution and formulating pollution control measures in Northeast China.