Abstract: Using the large-scale dynamic triaxial apparatus, a series of cyclic drained triaxial shearing tests are performed on there kinds of rockfill materials with different confining pressures, consolidation stress ratios and dynamic stress amplitudes to investigate the particle breakage behaviors of rockfill materials under dynamic loads. The results show that the particle breakage rate of rockfill materials decreases with the increase of the strength of parent rock, and increases with the increase of the confining pressure, consolidation ratio and dynamic stress amplitude. The analysis of particle breakage can be divided into four stages according to the process of dynamic triaxial tests. The current particle breakage state and stress level have a certain influence on the subsequent particle breakage behaviors. In addition, during the process of dynamic load, the volume shrinkage of samples can reflect change of the particle breakage rate to some extent.