Vibration Assisted Burnishing (VAB) is an advanced burnishing form incorporating dynamic force resulting from vibration into burnishing not only to change the loading type and contact method to greatly reduce friction and wear, but also to produce an excellent nanocrystalline surface by severe plastic deformation induced by high speed impact. The expression describing the relation between decrease of surface roughness and ball burnishing force is given. The dynamic model of ball VAB is established. The relations between VAB depth, VAB force and VAB time and their maximum values are derived, and the required maximum power of the vibration generator is then obtained. The theoretical equivalent burnishing force of ball VAB is only about 47.55% that of conventional burnishing, which prove validity of ball VAB.