Abstract: A PSMA targeting peptide derivative for radiotherapy, which is a structural molecule developed for diagnosis or treatment of prostate cancer, as prostate-specific membrane antigen (PSMA) is a protein present on the surface of healthy prostate cells, which is often at a high level of expression on the surface of prostate cancer cells, and the molecular composition of PSMA inhibitor is mainly composed of glutamic acid, urea and lysine, in addition to the linker of the present invention, PSMA inhibitor can be combined with a chelating agent and truncated Evans Blue, which can be labeled with radionuclides Ga-67, Ga-68, In-111, Lu-177, Cu-64 or Y-90, used for image analysis and analysis of human prostate cancer tumor pattern as a new PSMA targeting peptide receptor radionuclide therapy (PRRT), and which has a longer half-life in vivo and is featured by specific binding of PSMA for radiotherapy diagnosis or treatment.