Although transferrin receptor (TfR) is widely accepted as a target for cancer therapy, few studies have elaborated on delivery efficiency of TfR. upon interactions with TfR-targeted nanomedicine. Here, a micellar system employing TfR-specific 7peptide (histidine-alanine-isoleucine-tyrosine- proline-arginine-histidine, HAIYPRH, 7pep) as the targeting moiety was constructed; and its endocytosis, intracellular trafficking as well as influence on TfR. expression and in vivo tumor targeting were explored in the MCF-7 tumor model. In contrast to unmodified micelles, 7pep modification enhanced the cellular uptake of micelles without altering endocytic pathways, and slowed down the trafficking of micelles to lysosomes without changing the final intracellular colocalization. Interestingly, cellular TfR level was increased by 7pep-moclified micelles. Furthermore, receptor saturation and recovery was observed in vivo. In conclusion, this study comprehensively investigated the bionano interaction between TfR. positive tumors and 7pep-modified micelles, and provided scientific information for cancer therapy with receptor-mediated nanomedicines.