Abstract: Objective To investigate the expression of hepatocyte growth factor(HGF)in gingival tissue of chronic periodontitis and its relationship with smoking. Methods A total of 110 patients with chronic periodontitis were collected as chronic periodontitis group, including 75 mild and moderate patients, and 35 severe ones, among whom there were 55 smokers and 55 non-smokers. Meanwhile, 110 patients with healthy periodontal tissue and third molar impacted tooth extraction were selected as the control group, including 84 non-smokers and 26 smokers. The expression levels of HCG mRNA in gingival tissue samples were detected and compared by real-time quantitative PCR. Results Compared with the control group, the expression level of HGF mRNA in the gingival tissue of the chronic periodontitis group was significantly higher(P < 0.05). The expression level of HGF mRNA in the gingival tissue of patients with severe chronic periodontitis was significantly higher than that of the mild to moderate group(P < 0.05). HGF mRNA expression was higher in smokers than those without smoke in both the control group and experimental group, and was the highest in smokers in chronic periodontitis group. There were significant between-group differences(P < 0.05)except for smokers and non-smokers in the control group(P > 0.05). Conclusion The increase of HCF expression in gingival tissue of chronic periodontitis is related to the degree of periodontitis. Smoking can lead to increased expression of HCF in gingival tissue.