Abstract: The calcareous sand was taken from the sea areas near Nansha Island, mostly coral reef debris. It was an unconsolidated loose particle aggregate, which was easy to produce particle breakage. In order to study the influence of calcareous sand particle crushing characteristics on its compression characteristics, the one-dimensional compression test of calcareous sand was carried out under repeated loading-unloading conditions, and the compression characteristics was analysed. The particle breakage of calcareous sand in the process of repeated loading-unloading was evaluated by using the relative breakage rate B_r as the measurement index. Meanwhile, the plastic work of calcareous sand in the process of repeated loading-unloading was obtained according to the test data. By establishing the relationship between the plastic work and the relative breakage rate, the influence of particle breakage on one-dimensional compression characteristics was discussed. The results show that particle breakage increased significantly with the increase of loading pressure, and the process of particle breakage was obvious stress history dependent; with repeated loading-unloading, the increase of particle breakage rate became smaller and smaller; meanwhile, the relationship between particle breakage rate and plastic work of calcareous sand presented a power function, and the change rate of particle breakage rate gradually decreased with the increase of plastic work.