Abstract:This paper presents an analysis of the theory of spatial color decay including Lambert Beer law of atmospheric decay theory, particle scattering theory and so on. By selecting different atmospheric visibilities and various observation distances, an experimental research is conducted on architectural color decay law. The results of research indicate that architectural color decay meets the Lambert Beer law, brightness and saturation decay with the increasing distance of observation in accordance with an exponential law and the decay are directly related to atmospheric decay coefficient, while color hue basically remains unchanged.