It establishes that inflammatory disorder of Th1 and Th17 cells promotes alveolar bone damage during periodontitis. It is proved that Galla Turcica has the function of anti-inflammation and immuno-modulation. We are going to uncover the potential effect of Galla Turcica in bone protection and T helper cell regulation during periodontitis. Experimental periodontitis animal models were chosen for the presented research. We recorded the bleeding on probing, tooth mobility, the alveolar bone resorption rate of target teeth, proportion of CD4 + T-bet + , CD4 + ror-γt + subsets in gingiva and peripheral blood, L-2, IFN-γ, IL-17, RANKL concentration in GCF and peripheral blood sera. In addition, we performed cell culture experiments to illustrate how Galla Turcica affects Th1 and Th17 cell differentiation and function. The proportion of CD4 + T-bet + , CD4 + ror-γt + subsets, and the mRNA level and concentration of IL-2, IFN-γ, IL-17, and RANKL in cultured cells or culture media were detected by real-time PCR and ELISA. We established that Galla Turcica administration not just remedies periodontal bleeding and tooth movement, but reduce alveolar bone resorption rate. Also, we find Galla Turcica administration reduced gingiva Th17 cell proportion and GCF RANKL, IL-17 concentration. In cell culture experiments, Galla Turcica decreases Th17 cell differentiation, and IL-17 transcription and secretion. Moreover, our study showed that Galla Turcica reduces STAT expression and phosphorylation, which prevent Th17 cell differentiation. The outcomes of our study highlight the functions and possible mechanisms of Galla Turcica engaged in periodontal inflammations, and reveal the considerable effect of Galla Turcica in regulating Th17 cell differentiation and their likely contribution to alveolar bone resorption during periodontitis.