© 2023 Institute of Food, Science and Technology (IFSTTF).Water kefir (WK) is produced using WK grains containing beneficial bacteria and yeasts. It has antibacterial, anti-inflammatory, anti-diabetic, anti-hyperlipidaemic, anti-ulcerogenic, and antioxidant effects. The purpose of the research was to determine the effect of WK on irritable bowel syndrome (IBS). In this study, thirty-two female Wistar-Albino rats aged 3 months were randomly distributed to four groups: the control group (C), the WK group, the WK group with IBS (WK + IBS), and the IBS group. Results indicated that the IBS groups had higher white blood cell, lymphocyte, monocyte counts, and procalcitonin levels. The findings of WK + IBS group showed that WK improved against IBS. TNF-α, NF-kB expressions, and histopathological results significantly decreased after receiving WK treatment. In conclusion, ingestion of WK has prophylactic effects on IBS as exhibited through an in-vivo murine model. The findings suggested that IBS may be prevented and treated with WK.