Cancer is a broad term for a class of prevalent diseases as one in three people develop cancer during their lifetime. Although, there are few success stories of cancer therapy, most of the existing medications do not lead to complete recovery. Because of the complexity of cancer, usually a single therapeutic approach is insufficient for the suppression of cancer growth and metastasis. Simultaneous loading and co-delivery of different agents with different physiochemical characteristics to the same tumors have been suggested for minimizing the dose of anticancer drugs and achieving the synergistic therapeutic impacts in cancers treatment. Intense work to develop nanotechnology-based systems as a suitable option for cancer treatment is currently underway. The purpose of this review is to provide an overview of the co-delivery systems based on polymeric nanoparticles including polymeric micelles, dendrimers, poly-d,l-lactide-co-glycolide, polyethylenimine, poly(l-lysine) and chitosan for efficacious cancer therapy.