The utility model discloses a stepless amplitude modulation vibration exciter of ball for vibrated roller, including hollow vibration axle, vibration axle one end is connected to hydraulic motor, and the other end is connected to hydraulic control unit through rotary joint, vibrates the epaxial fixed eccentric device who is used for adjusting the amplitude that is provided with. The utility model has the advantages that the whole structure is simple singly, symmetrical arrangement steel ball in vibrating an eccentric device who controls both ends, the steel ball is promoted by hydraulic oil by piston pushing, piston, and through one end input hydraulic oil, hydraulic oil is exported to one end in addition, and messenger piston pushing steel ball moves to the amplitude of pairing vibration wheel carries out infinitely variable control, and the vibrated roller's of being convenient for intelligent control maintains just that the cost of upkeep is low, convenient, has higher practicality and spreading value.