Meticorterone (Prednisolone acetate) were injected into joints of 33 cases of rheumatoid arthritis, 172 times in total, with better results. Although intraarticular injection of prednisolone is, at present, to be one of the most effective treatment for rheumatoid arthritis, one must pay attention at the appearance of general effect in frequent and abundant injection. Comparative studies were performed on the effects of intraarticular injectons of prednisolone T. B. A, (on twelve cases), hydrocortisone acetate and meticorterone. Prednisolone T. B. A. was proved markedly longer effect in local with minimum general effect, It was, therefore, thought that prednisolone T. B. A. was safest and most effective in intraarticular therapy on the rheumatoid arthritis.