The technique of target identification in the opacitas medium by using the Mueller matrix of the object was researched. Based on the different object has the different Mueller matrix and different polarization characteristics,the Mueller matrix's 16 matrix elements could describe polarization information of the object completely. The depolarization factor or a Mueller matrix element of the object is worth as the gray scale to a new image,and the image average value, the standard deviation, the information entropy and the variance of the image was evaluated. The experimental result indicated that this method can improve the image formation quality greatly.