The invention discloses a single image quick defogging method based on an improved atmospheric scattering model. The method, to solve the detects of an atmospheric scattering model, is characterized by, redefining atmospheric light and transmittance in an original scattering model respectively, and on the basis of the improved model, to begin with, carrying out scene segmentation on a fogged image according to fog concentration characteristics; then, by means of a corrosion method proposed in a He method, and through an averaging strategy, estimating scene incident light L; next, by maximizing contrast information of each scene, roughly estimating the scene transmissivity T, and providing a transmissivity adaptive adjustment mechanism based on environment characteristics to realize flexible defogging; and finally, providing a guided total variation model to carry out edge optimization on the initial estimation result, and importing the optimization result to the improved scattering model to restore a clear image. The method can effectively solve the problems of illumination non-uniformity, over enhancement and oversaturation and the like, and is superior to existing mainstream defogging methods in the aspects of defogging capacity, universality and defogging speed.