Aiming at the efficient rock breaking technology and theoretical challenges faced by the full section tunnel boring machine (TBM) under complex conditions of deep underground high confining pressure, systematically explorations of the energy evolution and dissipation characteristics of TBM dual disc cutters for rock breaking in deep ground were obtained. Based on Abaqus nonlinear finite element software, a numerical model of dual disc cutters for intrusion rock breaking was constructed to analyze the damage and energy evolution characteristics of rock mass under variable confining pressure conditions. The effects of confining pressure, uniaxial compressive strength of rock, disc cutter blade width, and disc cutter spacing on energy dissipation of rock mass were studied. The research results indicate that confining pressure significantly changes the damage and failure mode of rock mass. When the confining pressure is low, longitudinal damage development is dominant in the rock mass, and increasing confining pressure promotes lateral damage development, resulting in tensile shear composite fracture. When the confining pressure is 25 MPa, the energy sudden change dissipation rate reaches its peak and enters the energy stable dissipation stage at the earliest. The compressive strength of rocks is nonlinearly correlated with energy dissipation. When the penetration is greater than 1 mm and the compressive strength of rocks is 105 MPa, the energy dissipation rate is the lowest. Under this condition, rocks are prone to breakage. Under high penetration conditions, increasing the disc cutter blade width and disc cutter spacing can promote energy release within the rock mass and improve TBM excavation efficiency. The research results can provide theoretical basis for energy-saving and efficiency improvement of TBM excavation in deep engineering.