Over the past two decades, significant advancements have been made in the field of polymeric drug delivery systems. These systems are defined as formulations or devices that enable the introduction of therapeutic substances into the body. The development of biodegradable and bio-reducible polymers has been instrumental in the creation of new drug delivery systems, offering promising future prospects for practical applications. Natural polymers (arginine, chitosan, etc.) have been extensively explored for polymeric drug delivery systems due to their biocompatibility and biodegradability. Synthetic polymers (poly(ethylenimines), biodegradable and bio-absorbable polymers, etc.) have also been studied for their potential in drug delivery. Efforts have been made to develop targeted polymeric drug delivery systems that can specifically deliver drugs to desired sites, reducing side effects and improving therapeutic outcomes. The rapid development of polymeric drug delivery systems based on natural and synthetic polymers is revolutionizing the pharmaceutical field. Significant progress has been made in using biocompatible and bio-related copolymers and dendrimers for cancer treatment, particularly as delivery systems for potent anticancer drugs. Combining insights from synthetic and biological fields is expected to lead to new paradigms in the design of polymeric drug and gene delivery systems, enhancing their efficacy and safety.