Abstract: A numerical analysis has been conducted to evaluate the damage evolution and the fracture process of brittle rock under different confining pressures by using RFPA 2D . A fractal dimension D  associated with material damage is defined to describe the damage process of the specimen subjected to tensile or compressive load.It is found that the fractal dimension D  and the damage variable ω increase progressively with loading. The initial damage is delayed by the increase of confining pressure. The results show that the specimen is strengthened by the confinement and fails according to Mohr-Coulomb failure criterion.