Cancer is a wide group of diseases and generally characterized by uncontrolled proliferation of cells whose metabolic activities are dtsrupted. Conventionally, chemotherapy, radiotherapy, and surgery are used in the treatment of cancer. However. in theory, even a sing/c cancer ce/I may trigger recurrence. The ref ore, these treatments cannot provide high survival rate for deadly types. Identijication of alternative methods in treatment of cancers is inevitable because of adverse effucts of con ventiona/methods. In the last few decades, nanotechnology developed by scientists working in different disciplines physics. chemistry, and biology offers great opportunities. It is providing elimination of both circulating tumor cei/.v and solid cancer cells by taryeting cancer cells. In this chaptem; inadequate parts of conventional treatment methods, nanoparlicie types used in new treatment methods of cancer. and targeting methods of nanopartic/es are summarized: furthermore, recommendations of future are provided.