Polymersomes are artificial nanoparticles formed by the self-assembly of amphiphilic block copolymers, which can encapsulate both hydrophilic and hydrophobic molecules. Their tunable composition allows for control over characteristics and properties, making them suitable for drug delivery, diagnostics, and bioimaging. Various preparation methods, such as direct hydration, thin film hydration, electroporation, and microfluidic synthesis, impact the characteristics and stability of polymersomes. Different types of polymersomes, including theranostic, targeting ligand-decorated, stimuli-responsive, and porous polymersomes, have been developed for specific applications. Despite their advantages, challenges such as stability, efficacy, and safety need to be addressed. The regulatory issues surrounding polymersome formulations have hindered their clinical trials and market entry. This review covers the definition, synthesis, and applications of polymersomes, highlighting their potential in improving therapeutic outcomes for various diseases, particularly cancer.Polymersomes are artificial nanoparticles formed by the self-assembly of amphiphilic block copolymers, which can encapsulate both hydrophilic and hydrophobic molecules. Their tunable composition allows for control over characteristics and properties, making them suitable for drug delivery, diagnostics, and bioimaging. Various preparation methods, such as direct hydration, thin film hydration, electroporation, and microfluidic synthesis, impact the characteristics and stability of polymersomes. Different types of polymersomes, including theranostic, targeting ligand-decorated, stimuli-responsive, and porous polymersomes, have been developed for specific applications. Despite their advantages, challenges such as stability, efficacy, and safety need to be addressed. The regulatory issues surrounding polymersome formulations have hindered their clinical trials and market entry. This review covers the definition, synthesis, and applications of polymersomes, highlighting their potential in improving therapeutic outcomes for various diseases, particularly cancer.