This review article focuses on recent advancements in pH- and redox-responsive polymer nanocomposites for site-specific drug delivery in cancer therapy. These biomaterials are designed to respond to the tumor microenvironment, characterized by acidic cytosolic pH and elevated redox potential, enhancing therapeutic efficacy while reducing off-target effects. The article explores the design principles, fabrication methods, mechanisms of action, and future prospects of these dual-stimuli-responsive biomaterials. Key topics include the role of the tumor microenvironment, the importance of pH and redox responsiveness, and the challenges and opportunities in developing effective and safe polymer nanocomposites for cancer treatment. The review highlights the potential of these materials to improve personalized and targeted cancer therapy, offering hope for better patient outcomes.This review article focuses on recent advancements in pH- and redox-responsive polymer nanocomposites for site-specific drug delivery in cancer therapy. These biomaterials are designed to respond to the tumor microenvironment, characterized by acidic cytosolic pH and elevated redox potential, enhancing therapeutic efficacy while reducing off-target effects. The article explores the design principles, fabrication methods, mechanisms of action, and future prospects of these dual-stimuli-responsive biomaterials. Key topics include the role of the tumor microenvironment, the importance of pH and redox responsiveness, and the challenges and opportunities in developing effective and safe polymer nanocomposites for cancer treatment. The review highlights the potential of these materials to improve personalized and targeted cancer therapy, offering hope for better patient outcomes.