Abstract： Objective： To observe the clinical effect of modified Gegen Qinlian tang combined with tinidazole for periodontitis and its effect on inflammatory responses. Methods： A total of 78 cases of patients with periodontitis were selected and divided into the observation group and the control group according to the random number table method，with 40 cases and 38 cases in each group respectively. Both groups received initial periodontal therapy. The control group was additionally treated with tinidazole， and the observation group was additionally treated with modified Gegen Qinlian tang combined with tinidazole. Both groups were treated for 8 weeks. Before and after treatment， the Chinese medicine syndrome scores， periodontal clinical indexes [plaque index(PLI)， sulcus bleeding index(SBI)， probing depth(PD)， and attachment loss(AL)] and serum inflammatory factors [high-sensitivity C-reactive protein(hs-CRP)，tumor necrosis factor-α (TNF-α) and interleukin-1β(IL-1β)] in the two groups were observed，and the clinical effects were evaluated. Results：The total effective rate was 95.00% in the observation group， higher than that of 71.05% in the control group， the difference being significant(P＜0.05). Before treatment， there was no significant difference being found in the comparison of the Chinese medicine syndrome scores between the two groups(P＞0.05). After treatment， the Chinese medicine syndrome scores in the two groups were decreased when compared with those before treatment(P＜0.05)，and the above score in the observation group was lower than those in the control group(P＜0.05). Before treatment，there was no significant difference being found in the comparison of the levels of PD，AL，PLI and SBI between the two groups(P＞0.05). After treatment，the levels of PD，AL，PLI and SBI in the two groups were decreased when compared with those before treatment(P＜0.05)，and the above levels in the observation group were lower than those in the control group(P＜0.05). Before treatment，there was no significant difference being found in the comparison of the levels of serum hs-CRP，TNF-α and IL-1β between the two groups(P＞0.05). After treatment，the levels of serum hs-CRP，TNF-α and IL-1β in the two groups were decreased when compared with those before treatment(P＜0.05)，and the above levels in the observation group were lower than those in the control group(P＜0.05). Conclusion： Modified Gegen Qinlian tang combined with tinidazole has a definite clinical effect for periodontitis， which can reduce the clinical symptoms and inflammatory responses of patients， and improve periodontal injury.