Radionuclide therapy is expected to be a powerful tool for glioma treatment. Here, we introduce a novel nuclear nanomedicine based on polydopamine (PDA), incorporating fibroblast activation protein inhibitor (FAPI) and macrocyclic chelator (DOTA) for specific cancer targeting and 177Lu labeling. The synthesized nanoradiopharmaceutical, 177Lu‐DOTA‐PEG‐PDA‐FAPI, exhibits good stability in serum, saline and PBS over 5 days. 177Lu‐DOTA‐PEG‐PDA‐FAPI shows efficient specific uptake and internalization when incubated with U87MG cells. In vivo distribution visualized prominent accumulation and long retention ability of 177Lu‐DOTA‐PEG‐PDA‐FAPI at tumor sites after local administration. Moreover, 177Lu‐DOTA‐PEG‐PDA‐FAPI has satisfactory antitumor ability without apparent toxic and side effects observed from therapy assay and H&E staining. This study highlights the feasibility of using PDA as a nanocarrier for glioma endoradiotherapy by targeting fibroblast activation protein.