<p>Shale, characterized by its laminated and fissile nature, exhibits significant anisotropy due to its thin, easily split bedding planes. The mechanical properties of shale vary with bedding plane orientations, posing challenges in modeling its complex structure. Previous research often oversimplifies bedding planes by treating them as continuous, straight, and equidistant, neglecting the anisotropic effects of varied bedding plane orientations. This study addresses these limitations by developing a comprehensive methodology for establishing and calibrating a realistic hybrid bedding-plane DEM model for shale specimens, enabling more accurate prediction of mechanical behavior. The shale models incorporate accurate bedding plane representations through image processing. The bedding plane lengths follow a log-normal distribution, with the mean length (LN) of 1.22&#xa0;cm and the standard deviation (LN) of 1.05&#xa0;cm. A systematic calibration procedure was developed for the shale hybrid bedding-plane DEM model at the laboratory scale. The results demonstrate that the calibrated UDEC model not only replicates stress-strain behaviors but also accurately captures failure modes across bedding plane orientations. The calibrated micro-properties for the trigon and bedding plane contacts align closely with laboratory observations, highlighting the effectiveness of the hybrid bedding-plane DEM model. This study bridges the gap between shale’s complex structure and geomechanical simulations, providing a robust framework for accurate anisotropic modeling of shale specimens.</p>