Abstract: Visibility in poor weather condition is severely degraded by scattering of light due to suspended particles in the atmosphere such as haze and fog. In this paper, we propose defogging method from a single image based on depth estimation using blur. Formation of fog is the function of the depth. Estimation of depth information is under constraint problem if single image is available. Hence, removal of fog requires assumptions or prior information. The accurate thickness of haze or fog from a single image in these bad weather environments is still a challenging task In this paper a method is proposed to estimate the depth of the image based on blur estimation. In an image that includes objects in focus and out of focus are perceived with various blur. Measure of blur can be used for segmentation of image in terms of depth.