Nowadays, reinforced concrete (RC) flat slab system is used in many projects, even though, possibility of common problems in the slab-column connection that can cause a punching shear failure. Furthermore, an unbalanced moment may occur especially in the case of edge columns, which cannot be avoided. Therefore, in this study, the moment values have been considered. The most common procedure used to avoid this problem is punching shear strengthening, as it can increase joint strength capacity. 3D nonlinear finite element model (FEM) software, ABAQUS, based on the concrete damaged plasticity model, was used in order to investigate the punching shear reinforcement efficiency and study the connection behavior. The material model definition is necessary in finite element modeling to be appropriated [1]. A simulation of the FEM was compared with experimentally fifteen tested specimens, as investigated in [2]. Types, shapes, and cross-sectional area of the strengthening materials, as well as, the load eccentricity value, were the main studied parameters. The punching shear load-deflection relationship, the ultimate load, and the pattern of failure were demonstrated by this simulation. The numerical and experimental behavior comparison results obtained a reasonable response.