Abstract：Through numerical experiment method，the influence of rock cell characteristics and rock inhomogeneity parameter on the character of the complete stress-strain curve under uniaxial compression is studied with rigid testing machine. Rock cell characteristics reflect the relationship between stress and strain，such as pure-elasticity，elasto-plasticity，strain-softening and strain-hardening. The material in each element is treated as homogeneous and is not the same as other element. The elastic constants and failure strength are randomly assigned according to Weibull distribution. The inhomogeneity parameter ‘m’ reflects the initial heterogeneity of distribution of material properties. The study result indicates that rock inhomogeneity parameter, m, is the decisive factor of complete curve character under uniaxial compression with m≥6. On the contrary，with m＜6，the rock cell characteristics are the decisive factor of complete curve character under uniaxial compression. The difference between peak and residual strength of rock sample is increased with the difference of corresponding rock cell.
