This study aimed to explore the impact of dietary supplementation of Poria cocos polysaccharide (PCP) on the lipopolysaccharide(LPS)-induced intestinal inflammation, morphology, and barrier damage in broilers. A total of 240 1-day-old male Arbor Acre broilers were randomly divided into 4 groups in a 2 × 2 factorial design comprising PCP supplementation (0 or 2 g/kg PCP from d 1 to 23) and LPS challenge (intraperitoneal injection of 1.5 mg/kg body weight of LPS or the same volume of sterile saline at d 22). Our results showed that compared to the non-LPS-treated groups, the treated birds showed a decrease in the ADG, VH, V/C, and the expression of ZO-1, occludin, claudin 1, and mucin2 in the duodenum and jejunum (P < 0.05). However, dietary PCP supplementation significantly mitigated these effects (P < 0.05) except for mucin2 in the duodenum. Furthermore, LPS treatment increased the levels of sIgA and upregulated the mRNA abundances of IL-1β, IL-6, TNF-α, IFN-γ, TLR-4, and MyD88 both in the duodenal and jejunal mucosa (P < 0.05). Whereas, PCP supplementation significantly reversed the LPS-induced effects on these genes (P < 0.05) except for the TLR-4 and MyD88. However, LPS did not impact the expression of anti-inflammatory IL-10 in the duodenal and jejunal mucosa (P > 0.05). Briefly, this study implied that dietary PCP supplementation could ameliorate intestinal inflammation and mucosal damage of LPS-challenged broilers, improving broiler performance.