Abstract: A green brick includes a brick body that is further consisted of a lubrication adhesive and an aggregate. The lubrication adhesive and the aggregate are mixed and then applied by a specific pressure so as to form the brick body. The lubrication adhesive is consisted of an activating solution and a binder. The binder is blast furnace slag, agricultural waste ashes, or a combination of the blast furnace slag and the agricultural waste ashes. Thus, the blast furnace slag and the agricultural waste ashes that are originally to be discarded are now recycled to form the green brick, such that the environmental pollution caused thereby can be reduced to a minimum.