For the purpose of this study, four natural rock samples-namely, diorite, granodiorite, tonalite, and granite-are being investigated about their radiation attenuation. The elemental composition of the rocks was obtained through Energy dispersive X-ray spectroscopy (EDX) which examines the microstructural and localized area elemental analyses of the four rock samples. A Monte Carlo simulation (MCNP) was used to determine and evaluate the investigated samples. Additionally, the samples were validated by Phy-X software (within the energy range of 0.015 to 15 MeV), and experimental measurements were achieved through the utilization of an HPGe detector (0.060, 0.662, 1.173, and 1.332 MeV). The investigation was carried out using various parameters such as linear attenuation (µ) and others. Furthermore, the Fast Neutrons Removal Cross Sections (FNRCS) were calculated using theoretical methods. In the case of granodiorite, tonalite, diorite, and granite, the values of µ were found to range from 7.931 to 0.049, 31.922 to 0.061, 17.267 to 0.060, and 23.860 to 0.056 cm