The main purpose of this paper is to experimentally determine the all-fire shock initiation criterion of Hexanitrostilbene-Ⅳ(HNS-Ⅳ) explosive under the impact of a short-duration high pressure pulse. Up-down tests of three kinds of polyimide flyers with different thicknesses (12.5, 40 μm and 50 μm) were carried out using Exploding Foil Initiation system (EFIs) in order to determine the minimum all-fire charging voltage. Using Photon Doppler Velocimetry (PDV) technology, the impact velocity of the three flyers under their minimum all-fire conditions was obtained. On this basis, the interface pressure p, particle velocity u and duration τ of the three kind of flyers impacting onto HNS-Ⅳ explosive were calculated based on shock wave theory and dynamic simulation. Furthermore, the all-fire shock initiation criterion of HNS-Ⅳ explosive under the impact of short-duration high pressure pulse was finally determined by data fitting. Results show that the all-fire pⁿτ criterion for HNS-Ⅳ with charge density of 1.56 g·cm^-3 explosive is p^2.88τ≥7.21 in the range of 10-13 GPa and 4.0-8.7 ns.