Abstract: Human epidermal growth factor receptor-2(HER2) is a kind of transmembrane receptor with tyrosine kinase activity, and also is a biomarker highly expressed in various cancer cells, often indicating poor clinical prognosis. HER2 expression molecular imaging mainly utilizes the labeled-ligands'ability of specific binding with HER2, such as radionuclide, magnetic materials and fluorescent substances, by which the high-HER2 expressed lesions are shown. This technique provides a strong support for diagnosing HER2-expressed diseases, selecting patients who are respondent to HER2-targeted therapy and evaluating the therapeutic effect, and has become one of the hot spots in the research of precise treatment of tumors in recent years.