Objective The current study was designed to find out the effect of Glucosidorum Tripterygii Totorum(GTT) on the serum level of soluble interleukin-2 receptor(sIL-2R) in patient with ankylosing spondylitis(AS).Method 29 patients with active AS were selected to take GTT(1mg per kg) three times a day for one year.After that,its curative effect was evaluated.The serum level of sIL-2R of these patients was measured by sandwich ELISA method and was compared with that of normal subjects.Result The serum level of sIL-2R in active AS patients was obviously higher than that of the non-active AS patients.(P<0.01).The total effective rate of GTT on AS was 89.6％,while clinical relief rate 27.6％,obvious effective rate 44.8％,effective rate 17.2％ and non-effective rate 10.4％.The patients' serum level of sIL-2R after therapy was significantly lower than that before therapy except patients with no effect.(P<0.05).Conclusion GTT has positive curative effect on active AS patients and could cause obvious decrease of the serum level of sIL-2R.The serum level of sIL-2R can be used as an important index of activity of AS and as a guide of therapy.