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Measurements of the global distribution of the tropospheric NO2 column densities have become available with the GOME (Global Ozone Monitoring Experiment) and SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric Chartography) instruments. The spatial and temporal characters of NO2 over the North-South Transect of Northeast Asia (NSTNA) was analyzed using monthly averaged tropospheric NO2 column densities from GOME and SCIAMACHY measurements taken from April 1996 to December 2010. In addition to NO2 (1996-2010) column densities data, land-cover data and characters of NO2 concentration over different ecosystem have been analyzed over the NSTNA. The results indicated that the tropospheric NO2 column densities over the region show distinct regional and seasonal variation characteristics for between 1996 and 2009. The highest concentration was in winter and lowest in autumn. The data also presents zonal distribution and decreasing from northern to southern. Under the influence of the urbanization process, the highest NO2 column densities appeared at cities and metropolitan areas which are located in the north plain of China and the southern areas of the NSTNA. Moreover the lowest column densities appeared at the northern areas of the NSTNA. The tropospheric NO2 column densities have shown significant differences over other ecosystems. In addition, the higher NO2 column density was found over forest and grass land while lower values over lake, tundra and semi-desert. There are different characteristics in five land use types along with the NO2 column densities increasing year by year. The highest values appeared in winter over the forest, grass, lake and tundra while in summer over the semi-desert.