With the advent of biotechnological advances and knowledge of molecular and cellular biology, radioimmunotherapy (RIT) has become a highly promising oncologic therapeutic modality with established clinically efficacy, particularly in non-Hodgkin’s lymphomas. A brief review of the published literature on the clinical applications of radioimmunotherapy, is provided. In the other hands a series of radiolabeled peptides have been designed and optimized for tumor-targeted peptide receptor radionuclide therapy (PRRNT). Pre-clinical and clinical applications of PRRT have shown promising results on tumor response, overall survival, and quality of life in patients with several kinds of tumors. 90Y-DOTA-TOC and 177Lu-DOTA-TATE are two of the most common radiopharmaceuticals with ymptomatic improvements and complete clinical data. Several trategies have been designed to improve the therapeutic efficacy of PRRT. For instance, radiolabeled peptides could be optimized by the amino acid modification and radionuclide selection. Healthy tissue protective agents and multicycle procedures could effectively decrease the side effects of PRRNT. Furthermore, combination treatments, including PRRT combined with surgery, chemotherapeutic agents, or radiosensitizing agents could be applied to increase the effectiveness of PRRT.