In order to investigate the rock failure mechanism using the TBM disc cutters under different lithologies, the micro contact model considering bond size was implanted into the discrete element software, which to simulate the rock breaking process with different cutter points under four lithologies. The influences of the cutter points and different lithologies on the effect of rock breaking efficiency were investigated. The simulation results showed that the rock failure process under different cutter points can be divided into three stages: loading stage, unloading stage and residual leaping stage. Bond failure mode can be divided into two modes: tensile shearing failure mode and compressive shearing failure mode. The mean resistance of the cutters on rock failure process can be expressed by the peak normal force. It depends on the lithologies and increases with the increasing of the rock compressive strength. The rock breaking efficiency is evaluated by the bond breaking specific energy. For hard rock mass, the three-point cutters have the highest rock breaking efficiency, and it is more efficient to use single-point cutter for lower strength rock mass.