The discrete element method is an established method for considering discontinuous deformation behavior of joint systems. This paper provides a description of this algorithm used to model coupled hydraulic and mechanical effects of joints on rock mass behavior. The paper also describes Bistun rock slope stability analysis using empirical (SMR) and numerical (D.E.) methods. The behavior of the rock slope and rock blocks containing Bistun epigraph in grouting and groundwater flow has successfully simulated using UDEC (Universal Distinct Element Code) program. Finally, results have been presented and discussed on slope stability condition and grouting pressure
