The results of spectroscopic study on the gas plasma induced by a pulsed laser with wavelength of 1.06 μm are reported. The gas samples are pure nitrogen, pure oxygen and air, all at the atmospheric pressure, and the spectral range studied is from 300 nm to 900 nm. The results show that the spectra of laser-induced plasmas for the three kinds of gas samples are composed of continuous spectra and line spectra, the basic features of the continuous spectra and line spectra were given, the possible connections of these spectra features to the characteristics of the laser-induced gas plasma were discussed, and the differences of the laser-induced plasmas between pure nitrogen, pure oxygen and air samples were analyzed. The basic features of time evolution and space distribution for laser-induced plasma spectra were also given and the relations between these features and the laser-induced plasma characteristics were briefly discussed. These results are helpful for the better understanding of the laser-induced plasma characteristics, especially those related to the relaxation process and the recombination mechanism of the plasma after its production.