To explore the mechanism of Anchang Jieyu decoctiona by detecting its effect on the expression of IL  6, IL  13 and NF  kB in rats with ulcerative colitis(UC).Methods:Ninety Wistar rats were randomly divided into six groups(blank control group, model control group, Anchang Jieyu decoctiona low, medium, high dose group and Solfasalazine(5ASA) group). Except for the blank group, the other groups were given trinitrobenzene sulfonic acid(TNBS) to produce rat model of UC. Different groups were given different dose of drugs respectively. After 3 weeks administration, colon tissue of the eye morphology scores, IL6, IL13 content, and NFκB protein expression were detected.Results:Rats in Anchang Jieyu decoctiona low, medium, high dose group and 5ASA group showed varying degrees of improvement and ulcer healing(P<0.01 orP<0.05), of which the high dose group and the 5ASA were superior to others, but comparison between the two groups showed no statistical significance(P>0.05); In level of IL  6, TCM low, medium and high dose group and the 5ASA group were differently lower(P<0.05 orP<0.01). Among them, the high dose group and the 5ASA were superior to middle and low dose group (P<0.01), but no statistical significance had showed between the two groups (P>0.05); In level of IL  13, TCM high dose group and 5ASA group were differently increased (P<0.01 orP<0.05), especially in high dose group. Besides, compared with 5ASA group, there was significant differences(P<0.05); In level of NF  kB, TCM medium, high dose group and 5ASA group have declined (P<0.05 orP<0.01), in which the effect of high dose group performed the best. While compared with 5ASA group, there were no statistical significance (P>0.05).Conclusion:Anchang Jieyu decoction performs better in antiinflammation and ulcer repair promotion. This may through down regulating proinflammatory cytokines IL6, up regulating antiinflammatory cytokines IL13, and inhibiting the expression of NFκB, which contribute a lot to the treatment of UC.