The relationship between particle crushing and grain group transformation under different loading conditions and stress levels of coral calcareous sand(CCS) from Xisha islands is investigated in this study. A series of tests were carried out,such as the oedometer test,triaxial compression test,simple shear test and cyclic shear test. The growth rate of particle crushing is adopted to analyze the crushing behavior of particles. The results indicate that the crushing growth rate of CCS decreases rapidly to zero with the increasing of loading cycles. The increasing of stress level accelerates the reduction of the growth rate of particle crushing,and arrives at the stable state of crushing sooner. It is proposed according to the test results that the particle crushing reaches its limit when the particle crushing growth rate is less than a small value. The limit value can be used in engineering practice. The mechanical parameters of the CCS corresponding to the limit value can be used as the extreme value in the design for the most unfavorable or most favorable situation in real project. Samples with higher contact force but insufficient relative motion between particles are lack of regularity in particle group transformation after crushing,while the samples with full relative motion between particles have the particle group transformation with obvious similarity and good regularity. The particle size of 0.25 mm is a critical point where the grain group content will be changed from variation to a stable growth state. The distribution of particle crushing can be divided into domains of particle size increasing and particle size losing. The particle size losing domain is correspond to the inflection interval of particle distribution curve under the same coordinate model of particle size.