Objective: To evaluate the efficacy of scaling and root planing (SRP) with a periodontal endoscope in the treatment of residual pockets in patients with periodontitis after initial periodontal therapy., Methods: Patients with residual pockets [probing depth (PD)≥5 mm] were included and randomly assigned to the endoscope group (SRP with a periodontal endoscope) or SRP group (SRP alone). The PD, attachment loss (AL), and bleeding on probing (BOP) of residual pockets were recorded before treatment and at 3 and 6 months after treatment. Data were analyzed with SPSS 20.0 software., Results: Compared with the baseline values, the percentage of PD≥5 mm sites, PD, AL, and BOP (+)% in the endoscope group and SRP group at 3 and 6 months after treatment decreased (P<0.05). Compared with the values at 3 months after treatment, the percentage of PD≥5 mm sites, PD, AL, and BOP (+)% at 3 and 6 months after treatment decreased in the endoscope group (P<0.05), whereas no statistical difference in these values was observed in the SRP group (P>0.05). Compared with those in the SRP group, the percentage of PD≥5 mm sites and PD at 3 and 6 months after treatment and AL and BOP (+)% at 6 months after treatment in the endoscope group decreased (P<0.05)., Conclusions: SRP with a periodontal endoscope shows a better effect in improving the PD, AL, and BOP of residual pockets (PD≥5 mm) in patients with periodontitis after initial periodontal therapy and has advantages in improving the long-term curative effect of this therapy.