An impact-progressive mechanical system is considered.the type of periodic-impact motion is analyzed and the condition for judgement of progressive motion of system is put forward.the dynamic behavior and The influence of system parameters on progression rate are investigated by numerical simulations. The results indicated that grazing bifurcation point is the dividing line between two very different motion of the system, a grazing contact instability of motion occurs, one impact in the motion period vanishes and the motion transits into motion, or falls into long periodic or chaotic motion immediately;the maximum impact velocity and the largest progression of the system are found to occur for period-1 single-impact motion with the peak-impact velocity