Abstract: From the features of fracture and acoustic emission and the stress-strain behavior this paper indicates that the activity of a fault zone depends on the angle of the fault plane with soft sandwich and the axis of principal compressive stress. Our experiments provide evidence that as this angle is larger than 45℃, the process of fracture has three stages, and before main shock there occurred a number of foreshocks and took place apparent dislocation within the fault zone and its surroundings. On the other hand, as the angle is smaller than 45? these phenomena then would be disappeared.