We compared the characteristics of MRI imaging and US imaging on joint inflammation in patients with rheumatoid arthritis (RA) . MRI imaging is worth for diagnosis of RA at the early stage, evaluation of drug treatment effects, and a new measure for true remission. US imaging is also useful for estimation of therapy and a criteria for complete remission, and cheep machine. We hope that both imaging technologies will be a standard for diagnosis and therapy evaluation in RA patients.