The invention discloses a TfR (transferrin receptor) specific binding peptide CPU-312-03 and an application thereof. The binding peptide sequences and nucleotide sequences of CPU-312-03 are respectively GLSRAHQ and GGGCTTTCTCGGGCTCATCAG. Vitro experiments shows that the binding peptide can be bound with cells capable of highly expressing the transferrin receptor TfR, and the coupled fluorescein isothiocyanate (FITC) can be inoculated into cells in a target mode. The binding peptide disclosed by the invention can be used in the drug targeting vector with the transferrin receptor TfR as a target site and is of great significance for the development of tumor targeting medicines, the targeted therapy of brain-derived diseases and predicting and diagnosing of the occurrence and development of tumors with transferrin receptor TfR as a target.