In the northeast of Algeria, Souk Ahras area is known for the severity and spread of landslides, especially in Mechroha and Zaarouria municipalities. Stability analysis of landslides in these areas depends on the calculations of safety factor according to several parameters (physical, mechanical, geological…). The aim of this study is to investigate the parameters affecting the safety factor using the design of experiments (DOE) method, central composite design (CCD) and response surfaces methodology (RSM). These methods use parameter modeling and optimization to discuss a solution of landslide hazard by developing models of safety factor (Fs) considered as response. The other parameters adopted as input independent factors are geotechnical physical and mechanical parameters such as: the dry and wet unit weight (γd, γh), the water content (w), the plasticity and liquidity limits and the plasticity index (WL, WP, IP), the percentage of fine elements Ff (%) < 0.08 mm), the cohesion C and the internal friction angle (Phi). Obtained results show high correlations with a regression coefficient R2 of 0.88 and 0.93 in the two cases study and the predicted factor of safety model fit best to those obtained in the analytical and numerical modeling procedure. The final model is applicable to give reliable results on the safety factor of landslides.