Abstarct: Exact investigation of stability of the rock slopes against earthquake is one of the most complex issues in the field of stability of the rock structures. Now the reason of the complexity is great diversity in data collection and the relations between them in analysis of this issue, so the existing methods for investigating of seismic stability of rock slopes, like quasi-static and practical methods are consist of very simplifying assumptions. Recent developments in both hardware and software fields has solved many existing problems in dynamic analysis of rock slopes, such as three-dimensional behavior and materials nonlinear behavior. Also because of uncertainty existence in geometric parameters of discontinuities, there is not any unique and efficient solution for evaluation of stability of the jointed rock slopes. For this reason using possible methods can be useful. One of the possible methods is using discrete fractures network-discrete element method (DFN-DEM). Discrete fractures network’s model (DFN) show more realistic presentation of geometry of the discontinuities. This model is baxsed on stochastically peresentation of discontinuities system according to probability density function of the discontinuity parameters. Acting forces between blocks can be estimated by numerical methods like discrete element method (DEM). The aim of this study is using a discrete discontinuity network for actual production of joints and also dynamic-seismic analysis for jointed rock slopes in different conditions. In this study it has been tried for validating of the results, either in production of joints and model geometry or in the results of analysis and displacements, the case study of the slope near the Dam and powerhouse of Roodbar of Lorestan to be used. In the beginning and before conducting any analysis on the slope, joints and model geometry must be produced. DFN-FRAC3D software is used to produce joints. For validating, produced joints with the help of software have been compared with field measurements and results showed that geometric properties of the generated joint network have conformed well with real collected data of the actual joint. After producting joints and overall geometry of model, model static analysis with gaurding system must be analyzed. In static analysis for investigating the model validation, it has been tried to use some points as control points on slope’s surface for controlling displacements with numerical model which in reality these points are consist of some extensometers that have been installed for controlling and recording of slope’s displacements. Recording displacements with extensometers after conducting the guarding system has been done for controlling displacements and preventing from failure in the time of static and dynamic analysis. In order to implementing the gaurding system, according to record of span analysis, a 20 cm-thick laxyer of shotcrete as well as rockbolts with the length of 12 meters, has been used. Displacement vectors derived from numerical analysis show that results of numerical modeling in comparing with reality has acceptable accuracy. After the model validation, with considering to dynamic considerations, has been paid to model dynamic analysis under earthquake load with the help of Tabas earthquake’s horizontal mapping speed. The results of dynamic and static analysis as well as guarding system for different conditions of joints including the change of opening and friction angles have been calculated.