Structures in mountainous areas need to be protected against rockfall hazard to prevent possible fatal damages. In recent years, a new type of rock fence constructed of concrete-filled steel posts, wire ropes, and wire netting has been developing in Japan. To verify the performance of this rock fence, dynamic finite element analysis based on numerical models of two full-scale collision tests was conducted. The performance of energy absorbers, which are effective in preventing wire ropes from breaking, was investigated with respect to their configuration and corresponding energy-dissipation behavior. In numerical simulation, a commercial finite element code featuring explicit dynamic capabilities was employed. The numerical results were compared with experimental data and good agreement was recognized in both cases. The results of numerical simulation have highlighted limitations of the testing method. In other words, the numerical results have provided a deeper understanding of the structural behavior and functions of individual components of the rock fence during rockfall impact. More importantly, numerical simulations can be used as supplements to or substitutes for full-scale tests, particularly in parametric studies and in design and redesign work.