The vertical column abundance of atmospheric NO 2 was measured with ground based solar spectra and a reference extraterrestrial spectrum in the visible wavelength range of 430—450 nm. The vertical column abundance and its variations of NO 2 in the region of Hefei were obtained from the measuremental data from the November to the end of December of 1999. The variation trends basically coincided with the surface density of NO 2 measured independently with conventional instruments on the ground. The instruments

principles of measurement and some of results were introduced.