Chitosan, a cationic polysaccharide, has prompted the continuous impetus for the development of tumor targeted drug delivery systems, thanks to the polymer's biocompatibility, low toxicity, and biodegradability. The presence of primary hydroxyl and amine groups on its backbone allows it for chemical modifications to control its physical properties. The nanomedicines prepared from chitosan and its derivatives can be delivered through different routes, such as oral, intravenous, and intraperitoneal. Chitosan-based nanomedicines including nanoparticles, microspheres, drug conjugates, micelles, hydrogels, etc. are in various stages of development. This polymer is being currently investigated for simultaneous delivery of two chemotherapeutic agents or chemotherapeutic agent with a gene carrier to produce synergistic effects. This chapter summarizes the recent advances in application of chitosan and its derivatives as a carrier for chemotherapeutic agents as well as gene carriers for cancer chemotherapeutics.