This study aimed to examine the behavior of a nailed soil slope under different conditions of the surcharge load based on numerical modeling. The numerical analysis process was performed using FLAC^3D difference element software. In this regard, effect of three different types of surcharge loads under different conditions was investigated for factor of safety of slope, maximum nail force, horizontal and vertical displacements of slope edge using static analysis. The surcharge loads included a distributed load of different values at a distance of 2 m from the slope edge, a particular line load at different distances from the slope edge, and different values of a point load in the middle of the slope edge. The results showed that the maximum nail force increased with increasing the distributed load. In addition, by increasing the distance of the line load from the slope edge, the maximum nail force decreased. Moreover, the horizontal displacement of the slope edge was found to increase with increasing distributed and point loads, whereas it decreased with increasing line load distance from the slope edge. According to the results, it was found that the distributed loading of 100 kPa at a distance of 2 m from the slope edge was the most critical one. The factor of safety value for this loading was equal to 1.27 and less than the allowable limit (1.35). In addition, the horizontal displacement in this type of loading was equal to 22.8 mm and more than the allowable limit (18 mm).