Obgective To investigate the short-term effects of improved percutaneous transforaminal endoscopic discectomy (PTED) in the treatment of patients with lumbar disc herniation and grade i spondylolisthesis. Methods 57 patients with lumbar disc herniation and grade i spondylolisthesis who underwent improved percutaneous transforaminal endoscopic discectomy (PTED) from January 2018 to December 2019 were enrolled. Visual analogue Scale (VAS), Oswestry Disability Index (ODI) and vertebral body slippage (%) were compared among the patients before surgery, 3 and 12 months after surgery. Meanwhile, the improved MacNab method was used to evaluate the efficacy in the12th month after surgery. Results All the operations were completed successfully, and there was no nerve injury, infection or other serious complications. VAS and ODI score of postoperative patients were significantly different from those before surgery (P < 0.05), and there was no significant difference between 3 months and 12 months after surgery (P > 0.05). There was no significant difference in the vertebral body slippage (%) before surgery, 3 and 12 months after the operation (P > 0.05). At the last follow-up, the excellent, good, fair and poor rate of the modified MacNab standard were 36, 15, 3 and 3 cases, respectively, with a good-to-excellent rate of 89.47%. Conclusion Improved percutaneous transforaminal endoscopic discectomy is safe and effective in the treatment of patients with lumbar disc herniation and grade i spondylolisthesis, which is worth clinical reference.