The limitations and disadvantages of current shielding materials (such as the high weight of lead, cracking and porosity of concrete, corrosion and toxicity of metals, and low flexibility of polymers) have led to an increasing interest in nanocomposites for protection against ionizing radiation in industry and medicine. In the meantime, nanocomposites have been introduced as effective and lightweight shields for gamma and neutron rays due to their superior mechanical properties and high efficiency in beam attenuation. Key factors such as natural abundance, simplicity in the nanocomposite fabrication process, high atomic number (High-Z) of the constituent metals (and their effect on photoelectric absorption and pair production mechanisms leading to reduced radiation flux), density, as well as cost-effectiveness play an important role in the selection of shielding materials. Considering these factors, this study evaluates the protective performance of nanoparticle-modified concrete, which was manufactured in the Concrete Reference Laboratory at the Standard Research Institute and reinforced with tungsten oxide (WO₃) nanoparticles and epoxy resin, against gamma radiation emitted from a cobalt-60 source (with energies of 1.17 and 1.33 MeV).. This improvement is due to the effective scattering and absorption of the rays by the high atomic number nanoparticles in the composite matrix. Accordingly, nanostructured shields with an optimal weight percentage and lower thickness can effectively replace thicker conventional concrete shields, which leads to space savings, weight reduction of shielding structures, and increased efficiency in medical and industrial applications.