The purpose of this study was to examine the effect of intermittent heat stress on muscle dysfunction in adjuvant-induced arthritis（AIA） rat. Rats were divided into four groups（n= 6 in each group）: a control（C）, heat stress（C+H）, AIA（A）, and AIA with heat stress（A+H） group. AIA was induced by an injection of complete Freund’s adjuvant to the knee joint cavity. Rats in the C+H and A+H groups were exposed to heated water at 42℃ for 30 min every other day. After 21 days of injection, extensor digitorum longus（EDL） muscles were removed and analyzed for force production and immunobloting. Compared with C group, the maximum specific force was decreased in the EDL muscles from the A and A+H groups. Moreover, the reduction in force production was accompanied by increased expression of TNF-α, 3-nitrotyrosine content, and actin aggregates in these groups. The levels of HSP72 were markedly increased in the C+H and A+H groups. There was no difference in the expression levels of HSP25, αB-crystallin, superoxide dismutase 2, and catalase between the groups. These results suggest that the increased HSP72 expression by intermittent heat stress does not ameliorate muscle dysfunction and inflammatory redox stress in AIA EDL muscles.