To explorer the serum level of pro- and anti-inflammatory cytokines in the patients of ulcerative colitis and irritable bowel disease. And analyze the correlation between the cytokine's levels and disease's activity of ulcerative colitis patients. Serum cytokines of ulcerative colitis and irritable bowel syndrome with diarrhea patients including IL-6, IL-10, IL-13, IL-17, TNF-α and TGF-β were analyzed by enzyme linked immunosorbent assay, and ulcerative colitis activity were assessed by Mayo scoring system. The correlation of the serum level of cytokines and ulcerative colitis activity were analyzed by the SPSS 19.0 software. Compared with healthy people, the serum level of IL-6, IL-10, IL-13, IL-17, TNF-α and TGF-β were elevated in ulcerative colitis patients. There is no direct correlation between each cytokines analyzed and the Mayo score. And the level of IL-6 is relevant to IL-13 (r=0.364, P=0.029), and the level of IL-17 is relevant to TGF-β (r=0.336, P=0.045). When the pro-inflammatory cytokines increase in the serum of ulcerative colitis, the anti-inflammatory cytokines were increased concomitantly, Some cytokines are positive correlated, such as IL-6 and IL-13, IL-17 and TGF-β, the mechanism of which is complex and needs further investigation.