Objective: To analyze the effect of different levels of root canal filling in the treatment of endodontics. Methods: Seventy-six cases of endodontics admitted to our hospital from September 2022 to September 2024 were included, and were divided into the experimental group (treatment with moderate filling program, n=38) and the control group (treatment with overfilling program, n=38) based on the method of randomized numerical table. The efficacy, number of painful teeth, masticatory function, complication rate and numerical rating scale (NRS), the MOS item short from health survey (SF-36) scores before and after treatment were compared between the two groups. Results: The total effective rate of 94.74% (36/38) in the experimental group was higher than 65.79% (25/38) in the control group (P < 0.05); after treatment, the NRS score of the experimental group was lower than that of the control group, and the SF-36 score was higher than that of the control group (P < 0.05); after treatment, the experimental group had fewer number of painful teeth than the control group, and the number of times of mastication was more than that of the control group, with a higher chewing efficiency than that of the control group (P <0.05); the complication rate of 2.63% (1/38) was lower in the experimental group compared with 28.95% (11/38) in the control group (P <0.05). Conclusion: Compared with overfilling, moderate filling used in endodontic root canal treatment can improve the treatment effect, can reduce pain, improve masticatory function, reduce the incidence of complications, and improve the quality of life.