There are many factors that may cause frequent fever in the elderly, which may be caused by the following aspects: 1. Frequent fever in the elderly may be caused by infectious factors such as pathogenic bacteria in the body, as the elderly have lower immunity and poorer resistance, they are easily infected with viruses or bacteria and cause frequent fever. 2. May be caused by non-infectious diseases, such as rheumatic immune system diseases in the elderly, such as rheumatoid arthritis. 3. 3.If elderly people suffer from malignant neoplastic diseases, it may also lead to frequent fever, such as stomach cancer, lung cancer, etc. 4.It may be caused by chronic infectious diseases, such as tuberculosis. Since elderly people are a special group, if they have frequent fever, they should go to the hospital for routine blood tests and other related examinations in time to clarify the cause and then actively treat it.