The influence of unloading confining-pressure on the failure Modes of Pillar was researched using Rock Failure Process Analysis(RFPA2D) developed by Northeastern University.The whole failure process of rock specimen under different conditions of unloading confining-pressure was simulated and analyzed,including stress accumulation,crack propagation and so on,and the failure law of pillar under unloading confining-pressure was obtained.The results of numerical calculation show that when the axial load is higher than the uniaxial compressive strength of rock specimen,once unloading of confining pressure easily causes violently brittle failure of rock,however,under step-by-step unloading of confining pressure rock specimens show obviously ductile character and the accumulated stress in rock specimen gradually releases,and the violently brittle failure of specimen would be avoided.The conclusion is valuable to the work of excavating in rock mass and maintaining the stability of stope and pillar in mine.