Abstract: In order to study the relationship between briquette preparation technique and performances and guide the optimization of the production technique, a si ngle polarized microscope and digital image processing technology were applied to two aspacts study, which the total void features and the horizontal and vertical void distribution features of the briquette prepared with different quality binder and different pressure, and to the deep analysis on the void diameter, location, orientation de gree and other features. The study results showed that the void rate of the briquette prepared with different quality binder and different pressure would be have big diffe rence. The horizontal and vertical void rates of the briquette would be different and the horizontal void diameter would be concentrated. The void distribution of the briq uette would be inhomogeneous and the orientation degree would be poor. The void of briquette from the surface to the internal would be in an increasing tendency.