Objective: To investigate the effects of minocycline hydrochloride ointment combined with tinidazole on serum C-reactive protein (CRP), tumour necrosis factor-alpha (TNF-alpha) and sputum fluid soluble intercellular adhesion molecule (sICAM) in chronic periodontitis patients. Methods: Ninety-eight patients with chronic periodontitis in our department of stomatology from June 2014 to March 2016 were randomly divided into a control group and a study group, with each group consisting of 49 patients. The control group was treated with minocycline hydrochloride ointment alone, and the study group was given tinidazole on the basis of the control group. Both groups were treated continuously for eight weeks. The clinical efficacy, serum CRP, TNF-alpha and sICAM-1, plaque index (PLI), periodontal adhesion level (PAL), periodontal pocket depth (PPD), tooth looseness (TMD) and gingival bleeding index (GI) before and after treatment in the two groups were recorded to observe the occurrence of adverse reactions in the two groups during treatment. Results: After treatment, the total effective rate in the study group was 93.88%, which was significantly higher than that in the control group (75.51%). This difference was statistically significant (P<0.05). The serum CRP, TNF-alpha and sICAM-1 after treatment were lower than those before treatment, and these indicators significantly decreased in the study group compared with those in the control group (P<0.05). The serum PLI, PAL, PPD, TMD and GI after treatment were lower than those before treatment, and these indicators significantly decreased in the study group compared with those in the control group (P<0.05). The rate of the adverse reactions occurred in the study group was 6.12%, which was significantly lower than that in the control group (28.57%); this difference was statistically significant (P<0.01). Conclusion: Minocycline hydrochloride ointment combined with tinidazole is effective in the treatment of chronic periodontitis, which can significantly improve the clinical symptoms of patients and reduce the serum levels of CRP, TNF-alpha and sICAM-1 with less adverse reactions and highly clinical application value.