The Archaeological Park of Pompeii offers a unique collection of Roman structures adorned with frescoes, buried by the eruption of Vesuvius in AD 79. Ongoing excavations continue to uncover new buildings that require appropriate interventions for consolidation and roofing systems. A crucial element in the design phase of these procedures is the estimation of the mechanical properties of the ancient masonry. As is not possible to know them directly through destructive in situ experimental tests, the use of the Masonry Quality Index (MQI) method, which correlates the masonry arrangement with its mechanical properties, is a viable approach. However, this method depends on visual survey, and is thus unsuitable for walls covered with plaster. This study investigates the potential of using high-frequency ground-penetrating radar (GPR) to reconstruct the masonry texture covered by plaster and frescoes in Pompeii. While GPR has been successfully employed to analyse masonry texture in other contexts, its performance strongly depends upon the electromagnetic characteristic of masonry needing a site-specific feasibility study. To establish the capability of using GPR in Pompeii to detect the masonry texture beneath plaster and frescoes, a preliminary in situ campaign and electromagnetic simulations were conducted. The results suggest that high-frequency GPR can successfully reconstruct the masonry arrangement, providing the necessary data for the application of MQI at Pompeii, offering a non-invasive solution for assessing the mechanical properties of ancient masonry in archaeological contexts.