Radiosynoviorthesis plays an important role in local treatment of rheumatoid arthritis. Radionuclides with different beta-energy are used according to the size of the joint. 90Y is used for the irradiation of chronic synovitis of the knee, 186Re for shoulder, elbow, wrist, hip and ankle; and 169Er for small finger joints. Side effects of radiosynoviorthesis such as irradiation synovitis can be avoided by synchronous injection of corticosteroids. About 60% of treated joints show good therapeutic results, early radiosynoviorthesis being the most successful. Best results are achieved in the early stages of disease in the treatment of ankle, knee and shoulder. Radiosynoviorthesis represents an alternative treatment for local therapy in rheumatoid patients.