ObjectiveTo simulate the expression of TNF-α and PGE2 of periodontal tissues in rat periodontitis model. Methods40 Wistar rats were randomly divided into the periodontitis group and the control group (n=20). After the successful establishment of periodontitis rat model, raising for six weeks before the animals were sacrificed. The periodontal tissues were obtained and made into slices. Observed the histopathological changes of the periodontal tissues and measured TNF-α, PGE2 levels change by immunohistochemistry, Western blot analysis and ELISA. ResultsTNF-α, PGE2 expression of the periodontitis group was significantly higher than that in the control group, the difference was significant (P<0.05). ConclusionsThe TNF-α, PGE2 expression of the rat periodontal tissue in the periodontitis group was significantly higher than the control group.