Abstract: Objective: To investigate the levels of the tumor necrosis factor (TNF-α), interleukin -17 (IL-17), interleukin -23 (IL-23) and their clinical significance in rheumatoid arthritis (RA) and chronic periodontitis. Methods: Twenty-eight rheumatoid arthritis (R) patients, 32 chronic periodontitis (P) patients, 22 rheumatoid arthritis and periodontitis (R+P) patients and 18 healthy persons (H) were selected according to the inclusion criteria. ELISA was used to detect the levels of TNF-α, IL-17, IL-23 in serum. Results: The levels of TNF-α, IL-17, IL-23 in groups P, H, and P+H were significantly higher than those of the control group (P<0.05); and the levels of TNF-α, IL-17, IL-23 in group P+H were significantly higher than those in group P and H (P<0.05). There was no significant difference between the group of P and H. Conclusion: TNF-α, IL-17 and IL-23 may be used as factors linking periodontal disease rheumatoid arthritis.