Abstract: A mounting bracket for a scope of a gun is disclosed. The mounting bracket is used to mount night scopes or telescopic scopes onto the barrel of a gun rapidly. The bracket comprises a seat body having a securing jaw, an actuating jaw and a triggering block, and the actuating jaw is pivotally mounted at the seat body and, together with the securing jaw, correspondingly grips the barrel of the gun. Further, the triggering block is pivotally mounted at the seat body, and the triggering block correspondingly urges or releases the actuating jaw. The user can rapidly disassemble the mounting bracket and the barrel of the gun. The direction of action of the triggering block is perpendicularly intersected with the vibration direction of the barrel and therefore the mounting bracket will not be dislocated in the course of shooting.