Resveratrol (Res) is a natural active antioxidant that is effective in relieving inflammatory bowel disease (IBD). However, the specific mechanism for its function is unknown. In our study, dextran sodium sulfate (DSS)-induced mouse IBD disease model was constructed. All mice were randomly divided into three groups. The treatment effects of resveratrol on IBD were evaluated by observing the body weight, fecal traits, colon/ spleen gross appearance, tissue hematoxylin-eosin (H&E)/immunohistochemistry (IHC) and inflammatory factors. The expression of small ubiquitin-like modifier protein 1 (SUMO1) and its Wnt/β-catenin pathwayrelated genes was analyzed by IHC, Western blot, Real-time PCR (RT-PCR) and Immunofluorescence. The outcome indicated that resveratrol treatment significantly relieved the symptoms of IBD. The expression level of anti-inflammatory cytokines was increased while that of pro-inflammatory cytokines was decreased in both colon and spleen tissues of resveratrol-treated mice. SUMO1 expression and Wnt/β-catenin pathway were suppressed in colon and spleen tissues of IBD mice treated with resveratrol. In addition, we provided evidence that resveratrol inhibited SUMO1 and β-catenin expression and their nuclear localization in human colonic epithelial cell line (FHC). Moreover, we found that SUMO1 and β-catenin had higher expression levels in colorectal cancer patients than in health and colitis patients. In conclusions, resveratrol alleviates DSSinduced IBD by modulating SUMO1 through Wnt/β-catenin pathway.