To study the mechanism of Sishen Pill（四神丸）in regulating immune balance and secreting inflammatory cytokines through Th17/Treg signaling pathway in the treatment of ulcerative colitis.

A total of 104 patients with ulcerative colitis diagnosed and treated in the hospital from August 2022 to July 2023 were selected and divided into two groups according to the random number table method，with 52 cases in each group. The patients in the control group were routinely treated with Mesalazine，and the observation group was treated with Sishen Pill on the basis of the control group. After 12 weeks of treatment，the efficacy，disease activity index score，immune indexes（Treg cell ratio，Th17 cell ratio and Th17/Treg value），inflammatory cytokines［interleukin（IL）-2，IL-6，IL-10，IL-17］and adverse reactions were observed and compared between the two groups

The markedly effective rate of the observation group was 86.54%（45/52），which was significantly higher than 69.23%（36/52）of the control group，and the difference between the two groups was statistically significant（P<0.05）. After treatment，the disease activity index scores of the two groups were significantly decreased，and the score of the observation group was significantly lower than that of the control group［（2.61±0.72）points vs（3.19±0.84）points］（P<0.05）. After treatment，the proportion of Treg cells in the two groups increased，the proportion of Th17 cells and Th17/Treg value decreased，and the indexes in the observation group were significantly better than those in the control group［（7.61±1.80）%，（6.35±0.41）%，（1.61±0.32）%vs（6.57±1.64）%，（7.67±0.52）%，（1.13±0.28）%］（P<0.05）. After treatment，the levels of IL-2，IL-6 and IL-17 in the two groups decreased，and the level of IL-10 increased. The above indexes in the observation group were significantly better than those in the control group［（5.39±1.13）pg/mL，（5.68±1.41）pg/mL，（53.82±5.20）pg/mL，（2.49±0.37）pg/mL vs（6.45±1.06）pg/mL，（6.62±1.70）pg/mL，（47.19±4.83）pg/mL，（2.98±0.30）pg/mL］（P<0.05）. No serious adverse reactions occurred in both groups.

By regulating the immune balance through Th17/Treg signaling pathway and regulating the secretion of inflammatory cytokines. Sishen Pills can significantly improve the symptoms of ulcerative colitis and play a higher therapeutic value.