Objective To evaluate the effect of Online-to-Offline (O2O) modelin oral periodontitis. Methods 200 periodontitis patients who were treated in dental clinic from May 2020 to May 2021 were selected as the control group. They returned to hospital for 4 times within one year after the completion of periodontal treatment, and 200 patients from June 2021 to June 2022 were selected as the intervention group. Based on treatment and follow-up in the control group, the Internet online and offline consultation mode was adopted. Results The probing bleeding percentage and plaque index in the intervention group were significantly lower than those in the control group during different follow-up times (P<0.05). By the end of follow-up, the total score and each dimension score of oral health care self-efficacy was significantly higher than those in the control group (P＜0.05), and the satisfaction of patients in the intervention group was 2.74±0.47. Conclusion The online-to-offline model can not only effectively control the level of plaque and gingival bleeding,but also improve the efficiency of oral health carein periodontits patients.