In this paper a finite element analysis of a flexible rockfall protection kit, designed for energies up to 100 kJ, is presented. The model was validated against a reference test which was also used to calibrate the material parameters of the cable net. With the presented method, starting from a reference experiment, the behavior of a rock fall protection system can be simulated with sufficient accuracy and reasonable computational costs. The code created for this purpose in the finite element package ABAQUS can easily be adapted and thus provides a solid basis for the adjustment of parameters for the simulation of rockfall tests. In a first stage the individual components of the system are modeled and tested. Also punching tests of network structures are briefly addressed. In the course of this work the punching test proved to be unsuited to reflect the behavior of the cable net structure appropriately. Finally the overall model is assembled, prestressed and loaded with a free-falling rigid body. With this model a parametric study of material properties of the cable net was performed until the results of the reference test were simulated within tolerable error limits. The importance of this tool lies in the fact that the entire system has been modeled and all relevant variables, such as anchor forces or deformations can be obtained as a result of the simulation. By means of a calibrated model numerous different, non-standard impact-events can be studied within short periods of time. Since such events cannot be replicated on the existing testing facilities but nevertheless occur in realistic situations, the proposed method can be used to increase the security level, reveal optimization potential and show possibilities for improvements.