Objective  To observe the effect of acupoint catgut embedding on the expression of inflammatory factor mRNA in cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) signal pathway of vascular dementia (VD) rats, and to explore the protective mechanism of acupoint catgut embedding on the brain inflammatory response of VD rats.    Methods  VD model was established by the modified Pulsinelli’s four vessel blocking method . Totally 148 male rats were randomly divided into VD model group, non acupoint catgut embedding group and acupoint catgut embedding group. On the 7th day after operation, catgut embedding at acupoints and catgut embedding at non acupoints were performed in the two treatment groups respectively, and materials were taken out 15 days later. Western blotting was used to detect the expression of COX-2 and PGE2, and real-time PCR was used to detect the mRNA expression of tumor necrosis factor α(TNF-α), intercellular cell adhesion molecule 1 (ICAM-1), interleukin(IL)-6, macrophage inflammatory protein 2 (MIP-2), IL-1β, and monocyte chemotactic protein 1 (MCP-1) in rat hippocampus.   Results Compared with the sham group, the expressions of COX-2, PGE2, TNF-α, ICAM-1, IL-6, MIP-2, IL-1β and MCP-1 in hippocampus of the other three groups were significantly higher (P<0.01). Compared with the model group, the expressions of COX-2, PGE2 protein and TNF-α, ICAM-1, IL-6, MIP-2, IL-1β, MCP-1 mRNA in the hippocampus of the acupoint catgut embedding group and the non acupoint catgut embedding group decreased significantly (P<0.01).   Conclusion  Acupoint catgut embedding can protect the brain from inflammatory injury by down-regulating the expression of related inflammatory factors in COX-2/PGE2 signaling pathway and reducing the inflammatory response induced by VD rats.