Rheumatoid arthritis (RA) is a common, frequently severe, chronic inflammatory disease. Although the cause of RA remains unknown, recent advances in understanding its pathogenesis have been substantial. Despite the use of a variety of medications, the treatment of RA is not fully effective in most patients. A T-helper type 1 (Th1)/T-helper type 2 (Th2) cytokine imbalance has been suggested to be of pathogenic importance in several diseases. In this review, the information of cytokine balance in both the experimental model of arthritis and patients with arthritis were summarized. Furthermore, to characterize the cytokine balance at a single cell level, we analyzed the subtypes of cytokine-secreting cells in an experimental model of arthritis using a dual color enzyme-linked immunospot assay (Stardust assay) which we newly developed. These information including our findings might provide us the clue for diagnosis and therapy of arthritis.