Objective To compare the application effect of multiple root canal therapy and one-appointment root canal therapy in patients with pulpitis. Methods A total of 94 patients with pulpitis who underwent root canal treatment in our hospital from July 2021 to July 2022 were randomly divided into control group and study group, with 47 patients in each group. The control group was treated with multiple root canal therapy, and the study group was treated with one-appointment root canal therapy. The clinical efficacy, pain and treatment satisfaction were compared between the two groups. Results The total effective rate of treatment in the study group was 100.00%, which was higher than 97.87% in the control group, but the difference was not statistically significant (P>0.05). The VAS scores of the study group were higher than those of the control group at 1 and 3 days after operation (P0.05). The treatment satisfaction of the study group was 95.74%, which was higher than 80.85% of the control group (P