As a pain physician, I see many patients with joint pain, and they often ask the doctor: Is this disease rheumatism? Or is it rheumatoid arthritis? It is clear that many patients often confuse these two completely different diseases. It is no wonder, however, that there are some similarities in the clinical manifestations of these two diseases, and lay people are inevitably confused about the concept. Today, we would like to give a brief explanation of these two diseases that can cause joint pain. Rheumatoid arthritis is a manifestation of rheumatic fever. Rheumatic fever is a systemic metabolic disease caused by group A, type B, hemolytic streptococcal infection, which often starts with a history of pharyngitis, dengue, and other infections. Rheumatic fever has a rapid onset and is most often seen in adolescents. Rheumatoid arthritis can invade the heart and cause rheumatic heart disease with fever, subcutaneous nodules and rash. Rheumatoid arthritis has two characteristics: first, the joints are red, swollen, hot, painful and cannot move, the onset of the site is often the knee, hip, ankle and other large joints of the lower limbs, followed by the shoulder, elbow, wrist joints, the small joints of the hands and feet are rare; second, the pain is wandering, a period of time is this joint attack, a period of time is that joint discomfort, but the pain does not last long, a few days can subside. The blood sedimentation is accelerated, the anti-“O” titer is increased, and the rheumatoid factor is negative. After treatment, recurrence is rare, and no deformity of the joint remains, while some patients may have heart disease. Rheumatoid arthritis is an autoimmune disease that is not hereditary, but may be related to genetic factors and occurs in women between the ages of 20 and 40. The early symptoms are mostly joint pain, swelling, stiffness, and difficulty in moving around, which may be mild or severe, recurrent, and persistent, often leaving behind ankylosing deformities of the bones and joints. Although a few patients may have cardiovascular disease, the majority of patients have no cardiac symptoms and are positive for rheumatoid factor.