Abstract: Study of oxygen-absorption coefficient in 5mm wave band is important for remote sensing of atmospheric temperature profile from satellite or ground. In order to obtain the atmospheric profile speedly and accurately, it is necessary to have a simple formula of oxygen-absorption coefficient. In this paper, the oxygen-absorption coefficient formula in a certain range of temperature-pressure and the oxygen-absorption coefficient formula of the standard pressure surface have been derived. These formulae may substitute for Meek-Lilley formula in remote sensing of atmosphere.