Conventional anticancer therapies, though still effective for treating cancer, have several drawbacks that can be overcome with the help of nanoparticles. In recent times, the focus has shifted to the utilization of a newer class of nanostructures called polymer-metal nanocomposites due to its combined diagnostic and therapeutic roles for high-efficient and low-toxicity anticancer therapies. Improper metal ion distribution or absorption in cells can stymie cellular functions, causing irreparable physical damage or triggering metabolic responses that lead to cell death. As a result, nanocomposites composed of metal nanostructure cores embedded in polymer matrixes/shells, show improved stability and excellent biocompatibility, making them better for targeting, drug delivery, therapy and cancer cell imaging. Therapeutic systems based on polymeric-metallic nanoparticles not only provide simultaneous diagnostic and therapy, but also allow for controlled and targeted drug release, revamping cancer treatment and management. This review is going to focus on various such polymer-metal nanocomposites and their therapeutic applications in enhancing targeted cancer treatment especially delivery of chemotherapeutic drugs. Furthermore, this review will delve into the utilization of metallic-polymer nanoconjugates/nanocomposites comprised of various metals such as gold, silver, bismuth, manganese oxide, iron/iron oxide, copper oxide, and others in the realm of cancer therapy. Additionally, an overview will be provided regarding the existing progress and development of these solutions through clinical trials.