Abstract:[Objective] To compare clinical outcomes of endoscopic posterior lumbar interbody fusion (Endo-PLIF) versus traditional open posterior lumbar interbody fusion (PLIF) for lumbar degenerative diseases [Methods] From January 2020 to June 2021, a total of 40 pa- tients received PLIF for lumbar degenerative diseases in our department. According to the results of preoperative doctor-patient communica- tion, 20 patients received Endo-PLIF, while the other 20 patients received traditional open PLIF. The document regarding perioperative peri- od, follow-up and images were compared between the two groups. [Results] All patients in both groups had corresponding PLIF performed smoothly without serious complications. Although the Endo group consumed significantly longer operation time and more intraoperative fluo- roscopy times than the open group (P<0.05) , the former proved significantly superior to the latter in terms of intraoperative blood loss, post- operative walking time and hospital stay (P<0.05) . However, there were no significant differences in the total incision length and incision healing grade between the two groups (P>0.05) . All patients in both groups were followed up for more than 12 months, and the Endo group re- gained full weight-bearing activity significantly earlier than the open group (P<0.05) . The VAS score for lower back pain and ODI score de- creased significantly (P<0.05) , while the JOA scores increased significantly over time in both groups (P<0.05) . At discharge, 6 months after surgery and at the last follow-up the Endo group was significantly better than the open group in abovesaid scores (P<0.05) . Radiographical- ly, intervertebral height and lumbar lordosis significantly increased 6 months after surgery and at the latest follow-up in both groups com- pared with those before surgery (P<0.05) , whereas which were not significantly different between the two groups at any corresponding time points (P>0.05) . In addition, there was no significant difference in Bridwell fusion grades between the two groups at the corresponding time points (P>0.05) . [Conclusion] he Endo-PLIF is effective treatment for lumbar degenerative diseases, with advantages of less trauma, less in- traoperative bleeding and faster postoperative recovery over the traditional open PLIF