The image enhancement method based on dark channel priori defogging performs well in target detection, but it takes the light intensity information as the carrier and the single optical dimension leads the target characterization efficiency to decline. Based on the sensitivity of polarization to physical properties, in this paper a proposal is made that polarization information is introduced into the traditional dark channel priori defogging method to enhance the recognition degree between different objects. The theory of backscattering and polarization detection in dark channel priori defogging method is studied, and the mechanical polarization filtering imaging equipment is built to verify the target characterization function of the proposed method in foggy environment. The research shows that the dark channel priori defogging method based on polarization can obtain the light intensity and polarization information of the object at the same time. Compared with the traditional dark channel priori defogging method, using the polarization difference between the target and the background can significantly improve their contrast. This research result can be applied to the existing polarization imaging instrument system to realize real-time backscattering and polarization information extraction, and further improve the efficiency of target detection and characterization in fog.