We undertook a study to assess the effects of Allium hookeri (AH) root and fermented root on inflammation and intestinal integrity of lipopolysaccharide (LPS)-challenged broiler chickens. Birds were assigned to six groups (n = 25 birds/treatment) and fed with basal diets (CON) or basal diets supplemented with AH root or fermented root at two concentrations (1 or 5%). At 7 d of age, five groups (n= 125) in each dietary treatment were injected with LPS (1 mg/kg body weight), and the remaining 25 birds were injected with sterile phosphate-buffered saline (PBS) as a negative control. LPS challenge significantly reduced average body weight gain at 24 h post-injection compared with PBS control. Fermented root supplementation increased average body weight gain by 1% compared with the LPS-challenged control. Serum α- 1-AGP levels, interleukin (IL)-1β, IL-8, tumor necrosis factor superfamily member 15 (TNFSF15), and LPS-induced tumor necrosis factor-α factor (LITAF) transcript levels were significantly higher in the small intestine in LPS-injected chickens. However α-1-AGP levels were reduced by AH root or fermented root (1 and 5%) supplementation and IL-1β, IL-8, and LITAF were also down-regulated by root and fermented root (1 and 5%) supplementation. The reduced expression of tight junction proteins (junctional adhesion molecule 2 (JAM2) and occludin) and intestinal mucin 2 (MUC2) by LPS challenge was reversed by root or fermented root (1 and 5%) supplementation. These findings demonstrate that dietary AH root and fermented root influence antiinflammatory activity and tight junction protein expression in LPS-induced chickens.