<p>Metastatic cancer remains a leading cause of cancer-related mortality, demanding more precise and effective therapies. Photothermal therapy (PTT), a minimally invasive technique that employs light-induced heat to ablate tumors, has attracted attention for its ability to target malignant cells while sparing healthy tissue selectively. Incorporating metallic nanostructures, such as gold, silver, platinum, palladium, iridium, and metal oxides, has enhanced PTT efficacy through their unique optical and thermal properties, which enable efficient near-infrared absorption and heat conversion. Beyond hyperthermia, many metallic nanoparticles induce apoptosis, generate reactive oxygen species, and modulate mitochondrial function. Surface modification further improves their biocompatibility, tumor-specific targeting, and potential for drug delivery. These nanoplatforms also serve as versatile systems for combination therapies with chemotherapy, immunotherapy, or gene-based treatments. This review highlights recent progress in metallic nanostructure-mediated PTT, underlying mechanisms, and future challenges, underscoring its promise as a cornerstone in personalized management of metastatic cancers. Recent studies further demonstrate that PTT not only ablates primary tumors but also significantly reduces metastatic burden and prolongs survival in preclinical models. The inclusion of metallic nanostructures with high photothermal conversion efficiency, optimized laser parameters (wavelength, power, irradiation time), and controlled metal content provides a foundation for durable anti-metastatic outcomes and long-term therapeutic benefit.</p>