Abstract: Based on the results of high pressure 1D compression laboratory tests on Toyoura sand,the cluster element which was formed by the contact-bond model in PFC2D was used to simulate the particle breakage characteristics of sand under high pressure.The high pressure 1D compression numerical tests were executed with the sample consisting of 887 clusters.It was indicated that the compression curve and the yield stress at the beginning of particle breakage achieved from numerical tests were both in good agreement with those of the laboratory tests on Toyoura sand.Compared with the laboratory tests,numerical tests could not only demonstrate the macro phenomenon of particle breakage,most importantly,it could also expose the regularity of evolution of particle breakage microscopically,and would contribute to the further research of the micromechanics of particle breakage.Finally,the sensitivity of the results of numerical tests to the variation of micro parameters,loading velocity,number of clusters and mean cluster size,was also investigated.