Multiple myeloma is a malignant plasma cell disease, also known as myeloma and plasma cell myeloma. It is a disease of middle-aged and elderly people. The median age of onset of patients in Europe and the United States is about 65 years old, and the median age of onset of patients in China is younger than that of patients in Europe and the United States, with a median age of 53 years old. The main manifestations of multiple myeloma are extensive bone destruction, recurrent infections, anemia, hypercalcemia, hyperviscosemia, and renal insufficiency. In today’s advanced medical science, why is it still difficult to diagnose multiple myeloma early? 1, multiple myeloma is a rare disease: there were many scholars who classified it as a difficult and rare disease, and non-hematologists have less chance to receive this disease and are not vigilant enough. 2. The clinical manifestations of multiple myeloma are diverse: sometimes the first symptoms of patients do not attract direct consideration of the disease, and if they are not alerted to the disease and undergo further examination, it is easy to misdiagnose or miss the diagnosis. 3. Multiple myeloma itself has no specific and typical clinical manifestations. 4.The clinical manifestations of multiple myeloma: some clinical manifestations often do not appear at the same time in the early stage, or some symptoms of other specialties appear. 5.Early stage of multiple myeloma: It often manifests as easy infection, bone pain, unexplained fever, fracture after minor trauma or pathological fracture without trauma, unexplained anemia, leukopenia, thrombocytopenia, proteinuria, and even renal insufficiency as the first manifestation (one or two of the above manifestations often appear). It has been reported that the misdiagnosis rate of multiple myeloma can be as high as 60%. Therefore, patients over middle age with unexplained increased hematocrit, anemia, recurrent infections, recurrent pneumonia, bone pain, proteinuria, and increased blood uric acid need to be highly alert to the possibility of this disease.