Abstract: Objective:To investigate the levels of Dkk1 in chronic periodontitis (CP), and explore the relationship between DKK1 and the occurrence and development of CP. Methods:Thirty CP patients were sub-divided into mild, moderate, and severe CP groups according to clinical attachment loss (CAL) and alveolar bone resorption data. Ten healthy volunteers were recruited as the control group. Gingival crevicular fluid (GCF) was collected from all people and the concentration of DKK1 in the GCF samples was detected using enzyme-linked immunosorbent assay (ELISA). Results: The concentration of Dkk1 in GCF of the CP groups (8.86±4.07)μg/L was significantly higher than that in the control group (5.51±2.05)μg/L (P<0.05). The concentration of DKK1 in the mild (5.17±1.49)μg/L, moderate (8.32±1.25)μg/L, and severe (13.07±1.80)μg/L CP groups increased significantly (P<0.05). There was a significant positive correlation between the concentrations of Dkk1 in GCF and PD, CAL. The mean optical density of Dkk1 in the gingival tissues of CP group was (13.40±2.83)×10^-2, in the gingivitis group was (7.95±4.52)×10^-2, in the control group was (5.31±1.40)×10^-2. The mean optical density of Dkk1 in the CP group was significantly higher than that in the gingivitis group and control group (P<0.05). The difference between the latter two groups was not statistically significant. Conclusion: Dkk1 may play a role in the development of periodontitis