Abstract: The optical information of object includes the polarization information in addition to the common spectral information. The acquisition of polarization information can achieve information extraction for a specific target in a complex background, especially the extraction of metal target information. Combined with the principle, composition and characteristics of polarization imaging, a common-aperture common-detector long-wave infrared polarization imaging system was used to extract the target information. Through simulation software analysis, the system can detect a vehicle target of 3 km away, and the imaging quality is good.