An analysis of the joint fluid should be performed as part of the diagnostic evaluation in any patient with joint disease. It is an important role in the differential diagnosis of the joint disease such as pyogenic arthritis, traumatic arthritis, degenerative and rheumatoid arthritis and others. The authors examined synovial fluid analysis in 33 cases of rheumatoid arthritis at the Department of Orthopedic Surgery, Chosun University Hospital. The following results were obtained. 1. The age and sex distribution was 21 cases in the male and 12 cases in the female. The sex ratio between male and female was 1.8:l. 2. The gross appearance of synovial fluid was greenish-yellow with turbid in 29 cases, and 4 cases were transparent with clear and yellow colored. The range of specific gravity was 1.028, it was more higher than normal values. 3. The range of white blood cell count in the synovial fluid was 5955/cubic mililiter in its average and polymorphonuclear leukocytes found the major part of cell counts (63.6%). 4. The glucose content in the synovial fluid was 72.8 mg/100ml in the range of average. It was tended to decrease compared with increase leukocyte numbers. 5. The latex fixation test in the synovial fluid was positive reaction in 93.9%, and was more higher value than its serum reaction in the blood. 6. The protein content in the synovial fluid was 6.9 gm/100ml) in the range of average, and it was 1.7 times more higher value than the reported literature. The correlationship of protein content between the duration of disease and its prevalences could not found the clinical significance. 7. The relationship between the age and the clinical course in the synovial fluid analysis was not significant finding of its fluid content and others, but the more pronounced pattern was revealed in the acute stage of rheumatoid arthritis in the joint fluid.