In this paper, we compare the validity of two approaches to simulate the FRP/concrete interfacial behavior of FRP shear-strengthened beams. In the first approach, the FRP/concrete interfacial behavior is modeled with two-dimensional interface elements. These elements are provided in directions parallel and perpendicular to fibers orientation. In this case, the bond-slip behavior between concrete and FRP is established on the basis of experimental results obtained from shear-lap specimens. In the second approach, the slip between concrete and FRP is simulated by one-directional truss elements aligned in a discrete manner. In this case, the bond-slip model of the FRP/concrete interface is a bilinear relationship. The accuracy of each approach to simulate the FRP/concrete interfacial behavior is investigated by comparing them with experimental results. The significance of both approaches is discussed.