Shrimp (Penaeus vannamei) powder/kappa-carrageenan (SP/KC) hydrogel was used to improve the anti-inflammatory efficacy of apigenin (API) with elastic gel properties and dense honeycomb microstructures. Ulcerative colitis (UC) mice were gavaged with API and SP/KC/API, respectively, to evaluate the effectiveness of SP/KC. Compared with API group, the weight loss and colon shortening of UC mice in the SP/KC/API group were alleviated from 35.8 % to 40.9 % and 14.7 % to 24.0 %, respectively. Furthermore, SP/KC/API positively affected the expression of oxidative stress and inflammation. Compared to API group, MPO and iNOS activities in colonic tissue decreased by 1.2-fold, and serum expression of TNF-alpha was reduced by 6.6-fold. In comparison with API, the anti-inflammatory IL-10 level in SP/KC/API group increased by 4.2 %. Moreover, the beneficial bacteria Verrucomicrobiota of SP/KC/API group presented a 39.3 % improvement over API group. These results suggested that SP/KC effectively improved the effect of API in alleviating DSS-induced inflammation in UC mice.