This dataset contains a reservoir model developed for high-fidelity numerical simulation using the CMG STARS reservoir simulator. This three-dimensional (3D) subsurface model is based on a geological framework which has been divided into a Cartesian grid. This grid provides the numerical basis for reservoir simulation. Key physical parameters have been incorporated into the model, including rock petrophysical properties, fluid properties and fracture geometries. These parameters have been derived from the interpretation of subsurface data acquired at the Groß Schönebeck geothermal research platform. To improve predictive reliability, the model was calibrated against field-scale hydraulic test data collected between 2011 and 2013. The numerical model is designed to simulate fracture-dominated enhanced geothermal system (EGS) scenarios within the Rotliegend reservoir. Its primary purpose is to evaluate the performance of different well layouts and multi-stage hydraulic fracture designs in terms of reservoir productivity.