The impulse wave is made by the weak normal shock discharge from an open end of a shock tube. In order to understand the dynamic characteristics of the impulse wave impinging upon a #at plate, experiments are performed over the shock Mach number range from 1)01 to 1)20. A #at plate is placed downstream, normal to the axis of the shock tube, to simulate the impulse wave impingement on an object. The distance between the exit of the shock tube and #at plate is changed. The ba%e plate is installed at the exit of the shock tube. The sizes of the ba%e plate and impinging #at plate are varied to investigate the magnitude of the impulse wave impinging upon the #at plate. Computational analysis is applied to model the #ow "eld subject to unsteady, axisymmetric, inviscid, compressible, equations. Computational results well predict the experimented dynamic behavior of the impinging impulse wave. The impulse wave impinging upon the #at plate has a sharp peak of very short rising time and its magnitude decreases with distance from the center of the #at plate. The magnitude of the impulse wave impinging upon the #at plate can be predicted by the empirical equations that are developed in the present study.