Her-2,3+ represents Her-2 protein positivity, which is commonly used in the prediction of the biological behavior of breast cancer and the determination of the effectiveness of anti-Her-2 targeted drugs. Her-2 protein is a transmembrane protein encoded by the human proto-oncogene Her-2, and Her-2 protein can be detected by immunohistochemistry.Her-2+ indicates Her-2 protein negative, Her-2++ indicates uncertain Her-2 protein negative and positive, and needs to be further confirmed by supplemental Fish test, and Her-2 +++ indicates Her-2 protein positive. Her-2 protein-positive breast cancers are more aggressive, have higher rates of recurrence and metastasis, and have a relatively poorer prognosis, but these patients are more sensitive to anti-Her-2 targeted agents (e.g., trastuzumab) and often benefit from them. In addition to breast cancer, the effect of Her-2 protein on tumor cells has also been discovered and concerned in other cancer types one after another, such as gastric cancer, colorectal cancer, etc. Patients are advised to actively cooperate with the treatment to avoid delays.