Abstract: Radioimmunotherapy (RIT) is the therapy which targeted to tumor cells using radiolabeled monoclonal antibodies directed against tumor-associated antigens. It has been one of the standard treatment options for patients with non-Hodgkin's lymphoma(NHL). The inefficient localization of radiolabeled mAbs to the solid tumors has refrained RIT from being applied to those diseases. Still, small volume or minimal residual disease has been recogenized as a potentially suitable target for radiolabeled antibodies. RIT appears promising for future cancer therapy.