Wahl’s macroglobulinemia refers to the abnormal proliferation of plasma cells, resulting in the secretion of large amounts of the pathological immunoglobulin IgM, which is called macroglobulin because of its large molecular weight. The course of macroglobulinemia is slow, with no clinical manifestations in the early stages, and may progress to anemia, enlargement of lymph nodes and liver and spleen, and hyperviscosity syndrome. Hyperviscosity syndrome is often caused by a large increase in monoclonal immunoglobulins, and may be characterized by dizziness, headache, visual disturbances, and in severe cases, heart failure, coma, and in some cases, amyloidosis. The main treatment is chemotherapy, mainly with alkylating agents, and if there is severe hyperviscosity syndrome that causes visual impairment and severe bleeding tendency, bloodletting treatment or plasma exchange can be considered to rapidly remove the abnormally increased macroglobulin, also known as immunoglobulin IgM, in the patient’s body. the cause of the disease is not well known, and there are no effective preventive measures, so early detection and early diagnosis are the key to good treatment. Early detection and early diagnosis are the keys to good treatment. It is also important to distinguish macroglobulinemia from multiple myeloma.