The Distinct Element Method (DEM) is a numerical technique that originally developed for discontinuum materials, and directly represents grain-scale microstructural features of rock like materials, such as pre-existing flaws, pores, microcracks and grain boundaries. These grain-scale discontinuities in the DEM model induce complex macroscopic behaviors without using complicated constitutive laws/equations. Therefore, the DEM model may be more realistic and appropriate representation of rock fracturing comparing with the other numerical simulation techniques.