Ki-67 detection index is 80% disease degree is more serious. Patients with malignant tumor tissue cell proliferation ratio relationship is very high, the degree of malignant development of the tumor is also higher, with very obvious recurrence, metastasis may be, the prognosis is poor. Simply elevated Ki-67 index only reflects the activity of tumor cells side by side, other immunohistochemistry results or pathological examination results have to be combined with the activity of tumor cells to determine the treatment of the tumor, such as lung cancer, breast cancer also depends on the size of the tumor, staging, the degree of metastasis of lymph nodes. If the positive rate of Ki67 reaches 80%, it is easier to recur for malignant tumors. 80% of Ki-67 detection index indicates that the malignant degree of the tumor is high, and invasion, recurrence and metastasis are easy to occur in the process of tumor development. If the Ki-67 index reaches 80% in advanced malignant tumor patients, they should be given active and effective anti-cancer treatment such as systemic chemotherapy, targeted therapy and immunotherapy to control the development of the disease.