lope stability has important role in mining and civil engineering activities. Decreasing of slope height causes increasing in factor of safety, and then decreasing in mining cost. Rock failure along discontinuity surface (including joints, faults and layers) occurs as a plane, wedge or block falling failure. While circular and gravel failure strongly takes place in weathered slopes. Stability analysis methods consist of experimental approaches (SMR and MRMR), limit equilibrium and numerical methods. Although extensive studies has been carried out on rock slope stability, but in the heterogeneous rock mass, few researches have been conducted due to the alternating of hard and soft layers and complicated behavior. In civil and mining investigations with heterogeneous rock mass, the first step involves determining of geomechanical parameters. Next step includes the modeling of rock slope surfaces, which can be modeled by three ways: actual layers, layer Equivalence and anisotropy state. There are three important topics in this research: how to extract geomechanical parameters for heterogeneous rock mass, modeling of rock slope surfaces (actual layers, layer Equivalence and anisotropy state). In addition, the effect of rock mass on the heterogeneous state was taken into account; this effect is due to the influence of some parameters such as increasing of wear layers thickness, layer and joint orientation and layers sequence. Then, their effect on safety factor and fracture level in slope surfaces was modeled by three methods; limit equilibrium with Slide software, continuous numerical method with FLAC and discontinuous model with UDEC. Results indicated that by increasing the percentage of weak layer thickness between strong layers to a certain limit, safety factor decreases. After certain limit, factor of safety remains constant by increasing of weak layer thickness. The modeling of layer orientation by three programs showed that, minimum safety factor corresponds to orientation angle 40 degree. Maximum safety factor corresponds to orientation angle 90 degree with Pro Slide and 80 degree with FLAC and UDEC. The modeling of layer sequence and layer thickness indicated that when weak layer thickness is 50 percent, by increasing the number of layers and decreasing thickness of them, factor of safety with limit equilibrium program increases to a certain limit, and then it remains constant. While in numerical programs, by increasing the number of layers, safety factor does not change, but whenever the thickness of weak layer decreases (about 20 percent), the variation of Confidence coefficient increases.