In order to characterize the propagation of detonation wave in small size charge, ultrafine HIVIX sample was pressed in small metal tubes and were initiated by detonators. The tested HIVIX was refined by and the run-up distance to detonation ranged from lOmm to 12mm, due to different diameters of charge and restraint condition. When the particle sizes decreased, the critical diameter and run-up distance to detonation reduced correspondingly. The numerical simulation was also proved by experimental results, and it was found different from the ideal models. The measurements of run-up distance to detonation were significantly depended on uniformity in small size charge