Objective To study the effect of the extract of total flavonoids of Chrysanthemum indicum (TFC) on adjuvant arthritis(AA) synoviocytes. Methods Totally 0.1ml of the complete Freund’s adjuvant was subcutaneously injected into the right hind feet pads of 20 SD rats. 24 days after immunity synoviocytes in the knee joint were treated with TFC. Cell morphology was examined with electron microscopy. Protein level of caspase-3 cleaved fragments was analyzed by Western blotting. The annexin V stain assay was applied to explore the effect of caspase-3 inhibitor on the amelioration in synovial cells apoptosis of AA rats. Results Typical morphology and biochemical feature of apoptosis in synovial cells of AA rats were observed with TFC. The protein level of caspase-3 cleaved fragments increased obviously and was related with the concentration of TFC in synovial cells of AA rats. The apoptotic cells positively stained with annexin V were markedly reduced by caspase-3 inhibitor. Conclusion TFC can induce apoptosis in AA rats synoviocytes，which may achieve therapeutical effects in AA. The activation of caspase-3 may