This study found through animal experiments that the Hippocampus abdominalis can effectively alleviate the symptoms of DSS‐induced ulcerative colitis and depressive‐like behaviors, mainly by reducing inflammatory cytokine levels, promoting neurogenesis, enhancing the expression of brain‐derived neurotrophic factor (BDNF), and reducing DSS‐induced mitochondrial damage. This evidence concerns the gene BDNF and ulcerative colitis.