ObjectiveTo establish an animal model of rheumatoid arthritis (RA) and isolate fibroblast-like synoviocytes (FLS) from inflammatory synovium. MethodsModified adjuvant was prepared using heat-killed Mycobacterium tuberculosis H37Ra with sterile mineral oil,and arthritis was induced in Lewis rats by injection of the adjuvant at base of tail. Synovial tissue specimens were taken from arthritic ankle joints followed by mincing adequately. FLS were isolated by collagenase digestion. ResultsArthritis was successfully induced in the rats. The incidence reached 100% with regular time of arthritis development, and the histological changls were similar to those of rheumatoid arthritis. FLS were successfully obtained,identified and characterized in vitro. ConclusionsAn animal model of RA has been successfully established in rats and FLS have been successfully obtained, providing a desirable in vivo animal model and in vitro cell model for exploration of RA pathogenesis and drug evaluation. 