<p>In this study, the macroscopic and fine-scale crushing mechanism of ore particle clusters under dynamic loading is systematically revealed through drop hammer impact tests and discrete element numerical simulations. The results show that: (1) Under a fixed number of crushing, the breakage rate of the ore particle clusters increases with higher drop hammer heights, while its compactness decreases. Conversely, at a constant drop height, both the breakage rate and compactness rise with an increased number of crushing. (2) In terms of crushing mechanisms, it was found that the fine-grain effect reduces the crushing rate of ore particle clusters, i.e., crushing produces fine particles that fill the voids of large particles, weakening the transfer of interactions between large blocks of ore due to the lack of friability of the fine particles. (3) The strong force chain within the ore particle clusters is transmitted in all directions along the contact action points and is influenced by the internal contact action points between the particles, the more contact points there are, the greater the internal force and the degree of fragmentation of the particle. (4) The ore particle clusters crushing process can be divided into layers of dense, layers of compression and material crushing three stages, reasonable to control the layer height is conducive to the inter-particle material to get better crushing.</p>