DOTA Conjugated JM#21 derivative 7 (compound Ligand-7) is a derivative of CXCR4 targeting peptide conjugated with DOTA and can be used to produce radioligands. Radiolabeled DOTA Conjugated JM#21 derivative 7, i.e., 177Lu-DOTA, has excellent CXCR4 tumor targeting. In vitro biodistribution results of 177Lu-DOTA showed very low uptake in all non-targeted organs except kidney. DOTA Conjugated JM#21 derivative 7 can be used for the synthesis/research of Radionuclide-Drug Conjugates (RDCs).