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Near Infrared airglow was observed in the altitude range 80-210km at a mid latitude (30°N) in the wavelength region between 2μm and 5μm. Two airglow components were found. One component is strong in the broad wavelength range at altitudes lower than 100km, which is considered to be due to OH Meinel bands, whereas the other component was detected in the altitude range higher than 110km. The intensity of the latter is too strong to be interpreted in terms of a current model of the thermosphere. If this is attributed to the 2.8μm band (Δν=2) of NO, the density profile of excited nitrogen atoms N(2D) can be derived from the reaction N(2D)+O2→NO+O. The absolute density thus derived is considerably higher than that obtained from NI (5, 200A) airglow and that based on a thermospheric model.