Vanillic acid, an oxidized form of vanillin, is a benzoic acid derivative used as a flavoring agent. The objective of this study was to determine whether vanillic acid has beneficial effects against dextran sulfate sodium (DSS)-induced ulcerative colitis. Our results showed that vanillic acid reduced the severity of the clinical signs of DSS-induced colitis, including weight loss and shortening of colon length, and the disease activity index. The results of this study showed that vanillic acid significantly suppressed the expression of cyclooxygenase-2 and the activation of transcription nuclear factor-κB p65 in DSS-treated colon tissues. In addition, we observed that the plasma levels of interleukin (IL)-6 were higher in the DSS-treated group than in the control group, but these increased levels were reduced by the administration of vanillic acid. Taken together, these findings suggest that vanillic acid has a beneficial effect on DSS-induced ulcerative colitis, thereby indicating its usefulness in the regulation of chronic intestinal inflammation.