Lactobacillus acidophilus L. acidophilus Lactobacillus, Bifidobacterium, and Akkermansia, This study aimed to explore the ameliorative effects and underlying mechanisms of oral administration Lactobacillus acidophilus 6074 fermented jujube juice (LAFJ) on dextran sulfate sodium (DSS)‐induced colitis in mice. In this study, jujube juice was used as a substrate and fermented by L. acidophilus 6074 to investigate its effects on gut microbiota, intestinal barrier function, oxidative stress, inflammatory factors, and short‐chain fatty acids (SCFAs) in mice with colitis and to reveal its potential mechanism for alleviating colitis. The results demonstrated that fermentation caused significant changes in the nutrients and nonnutrients of jujube juice, mainly in organic acids (malic acid, lactic acid, citric acid, and succinic acid) and free amino acids (Thr, Met, Ser, Ile, and Lys). High‐dose LAFJ (20 mL/kg/day) significantly reduced the disease activity index (DAI), improved histopathological morphology, and increased colon length in colitis mice. LAFJ alleviated colon damage and preserved the integrity of the colonic mucosal barrier by promoting the expression of colonic tight junction proteins occludin, claudin‐1, and zonula occluden‐1 (ZO‐1). Furthermore, LAFJ inhibited the production of proinflammatory factors and attenuated oxidative stress. Gut microbiota of mice revealed that LAFJ increased beneficial bacteria such as Lactobacillus, Bifidobacterium, and Akkermansia, promoted the production of SCFAs, and inhibited the growth of harmful microorganisms. Overall, LAFJ could reshape and restore gut microbiota imbalance caused by intestinal inflammation and alleviate the development of colitis, which may become a novel dietary intervention.