Abstract: The present disclosure relates to a multi-functional nanoparticle targeted to breast cancer, a preparation method and use thereof. The multi-functional nanoparticle includes a targeting carrier and a medicament loaded on the targeting carrier; and the targeting carrier is made from recombinant ferritin. Cell experiments verify that the multi-functional nanoparticle has better efficacy and drug release capacity for cancer cells than those of conventional ferritin as a vector. Moreover, the drug delivery system can further achieve optical imaging of tumor cells by loading quantum dots, thus playing a role in cancer diagnosis and treatment.