Metallic nanorods are promising radiosensitizers, with their effectiveness influenced by atomic number, mass density, and biological factors. This study investigates the radiosensitization efficacy of five different metallic nanorods - gold, platinum, hafnium, gadolinium, and cerium by using TOPAS Monte Carlo simulations. The spectra of emitted electrons from the nanorods under 100 kVp X-ray irradiation were studied. Additionally, we examined the radial dose enhancement ratio (DER) around nanorods and corrected for lateral charged particle equilibrium (CPE) to ensure the accuracy of our model. The results demonstrate that physical dose enhancement is highly localized, with significant differences between the examined nanomaterials observed within 300 nm from the nanorod center. This effect is attributed to low-energy Auger-Meitner and Coster–Kronig electrons (below 3 keV energy). However, DER profiles for all nanomaterials come together beyond this distance, with variations below 1% at distances greater than 1 μm. Gold and platinum exhibited the highest total DERs, whereas hafnium, gadolinium, and cerium showed less but competitive values, approximately 2–3.5 times lower. While materials with higher atomic numbers deliver greater localized dose enhancement, all examined nanorods show comparable efficiency at extended distances. The study emphasizes the importance of nanoparticle internalization in determining radiosensitization efficacy. It also highlights the need to balance physical dose enhancement with biological and chemical factors, such as biocompatibility, cellular uptake, and surface functionalization, when designing effective nanorod-based radiosensitizers.