Xylo-oligosaccharides (XOS) has a bidirectional regulatory effect, and can be fermented by gut microbiota. This study aims to investigate how XOS alleviates Folium Sennae extracts induced diarrhea in mice. KM mice are given different concentration XOS for 3 weeks, and then Folium Sennae (Senna alexandrina Mill) extracts solutions (0.8 g mL-1 ) are given to establish diarrhea model. The results show that doses of XOS at 0.25 mg g-1 BW day-1 and higher could alleviate diarrhea symptoms by decreasing the disease activity indexes, down-regulating pro-inflammatory factors, up-regulating anti-inflammatory factor, and suppressing the intestinal permeability in colon tissues. XOS also regulates the composition of gut microbiota via increasing the abundance Prevotellaceae, Ruminococcus, and Bifidobacterium. The results suggest that the dietary supplementation XOS could be a more effective choice to prevent and alleviate diarrhea.