Inflammatory bowel disease (IBD) including ulcerative colitis (UC) is one of the risk factors for the development of colitis-associated colon cancer (CAC). CAC is a type of colorectal cancer (CRC), the third leading cause of cancer death. Ziziphus jujuba (ZJ) fruit contains bioactive components such as polysaccharides, triterpenoid acid, and flavonoids, and it has shown anti-inflammatory property. The aim of the study was to investigate the protective effect of dietary ZJ on colitis-associated colorectal tumorigenesis in mice. Mice (n = 42, two sets) were injected with azoxymethane (AOM) followed by three cycles of 2% (w/v) dextran sulfate sodium (DSS) in drinking water to induce CAC. Simultaneously, those mice were fed with ZJ diet for 70 days (5% or 10% w/w). Data were analyzed by ANOVA followed by LSD Bonferroni test. Dietary ZJ decreased fecal blood, diarrhea, disease activity index (DAI), spleen weight (P < 0.001), and the number of tumors (P < 0.001). In addition, dietary ZJ increased colon length (P < 0.001) and suppressed the activation of NF-кB/IL-6/JAK1/STAT3 signaling pathway. In conclusion, we suggest that dietary ZJ attenuates inflammation by interfering NF-κB/IL-6/JAK1/STAT3 signaling pathway, thereby inhibits AOM/DSS-induced colon tumorigenesis in mice.