Abstract: Rocks continuously exchange energy and mass with the external environment in their deformation or fracture, and their thermodynamic state continuously changes correspondingly. The paper interprets the energy dissipation and release characteristics of rocks in deformation and fracture process with non-equilibrium thermodynamic theory. In the said process, the heat supply and the change in he shape and position of rock volume elements which are the energy source for the plastic strain hardening and micro-crack formation in rocks lead to the continuous growth of the micro-cracks dispersed in rocks, which develop gradually from disorderly to orderly and form macro-cracks. Macro-cracks  in turn concentrate in certain direction and finally form large cracks that lead to the integral instability. From the viewpoint of mechanics, it is, as a matter of fact, a process from local damage, to brushfire fracture and eventually to integral collapse. From the viewpoint of thermodynamics, this process from rock deformation, failure to collapse is an irreversible process of energy dissipation, including both energy dissipation and energy release. The rockmass collapse is essentially a whole process of energy dissipation and release, and the moment of collapse is mainly powered by energy release.

Key words: Rock, Energy dissipation, Instability-caused failure, Damage, Strength