MGUS is a monoclonal immunoglobulinopathy, a group of benign disorders in which monoclonal immunoglobulin present in the blood is less than 3 g/dL, as well as little or no monoclonal immunoglobulin in the urine, and the percentage of bone marrow plasma cells is less than 10%, without end-organ damage. The etiology of monoclonal immunoglobulinopathy is not clear, and may be related to genetic factors, environmental factors, radiation, chemicals and other factors. It is often characterized by symptoms such as anemia, bone destruction, abnormal kidney function, skin changes, and blood clotting abnormalities. If monoclonal immunoglobulin disease does not show obvious symptoms, usually do not need special treatment, only need to follow the doctor’s instructions every six months to review the M protein index, blood routine, blood creatinine, blood calcium and so on. In case of unexplained anemia, kidney injury, hypercalcemia, and bone pain, bone marrow aspiration examination and imaging examination should be performed, and targeted treatment should be carried out immediately. Therapeutic drugs include prednisone and cyclophosphamide. If the patient has the above symptoms, it is recommended to go to a specialized hospital for further examination and treatment under the guidance of a doctor after the cause of the disease is clarified.