Tumor fever refers to non-infectious fever related to tumor and fever produced after tumor treatment when infection is excluded and antibiotic treatment is ineffective in tumor patients. The duration of tumor fever varies according to its etiology, some tumor fever can last for several hours, some can last for one week, several weeks, several months or even one year. The causes of tumor fever are as follows: I. Tumor grows rapidly, causing fever after relative ischemia and necrosis of tissues. After treatment, tumor cells are destroyed in large quantities, releasing tumor necrosis factor to cause fever. The malignant tumor cells themselves release endogenous pyrogen, causing fever. Tumor cells secrete active substances, causing fever. Fifth, in the process of tumor treatment, radiotherapy, chemotherapy, application of interferon and other treatments can also cause fever.