Abstract:[Objective] To compare the clinical outcomes of non-fusion versus fusion pedicle screw fixation for multi-segment lumbar degenerative diseases. [Methods] A total of 62 patients with three-segment lumbar degenerative diseases were included in this study from January 2018 to December 2019. According to preoperative doctor-patient communication, 30 patients were treated with spinal decompres- sion and non-fusion pedicle screw fixation with PEEK rod, while the remaining 32 patients received decompression and conventional pedi- cle screw-rod fixation and fusion. The the latest follow-up [(5.2±3.4)° vs (6.3±3.2)°, P＜0.001; (5.3±3.7)° vs (6.7±3.8)°, P＜0.001], whereas significantly greater fixed segment ROM at 3, 12 months and the latest follow-up [(8.4±3.6)° vs (2.1±0.9)°, P＜0.001; (9.7±2.3)° vs (1.4±0.5)°, P＜0.001; (11.5±2.9)° vs (0.9±0.4)°, P＜ 0.001], and significantly greater overall lumbar ROM at the last follow-up than the fusion group [(26.2±6.8)° vs (23.4±3.5)°, P=0.012]. In ad- dition, the non-fusion group had significantly better Pfirrmann grade for the upper adjacent space at the last follow-up [I/II/III/IV/V: (5/15/7/ 3/0) vs (4/12/11/4/2) , P=0.014]. [Conclusion] The non-fusion fixation does remains partial motion of fixed segment with less stiffness of lumbar spine, which has relatively little impact on the degeneration of adjacent intervertebral disc.perioperative, follow-up and imaging data were compared between the two groups. [Results] Although there were no significant differences in incision length, postoperative drainage volume, incision healing grade, postoperative walking time and hospital stay between the two groups (P＜0.05), the non-fusion group proved significantly superior to the fusion group in terms of opera- tive time [(172.2±48.7) min vs (216.5±75.4) min, P＜0.05] and intraoperative blood loss [(216.5±75.4) ml vs (268.8±94.5) ml, P＜0.05]. With time of follow-up lasted for (28.1±3.8) months on a mean, the VAS scores for back pain and leg pain, as well as ODI and LSDI score signifi- cantly improved in both groups (P＜0.05). Despite of the fact that there were no significant differences in the VAS scores for lumbago and leg pain as well as ODI score between the two groups at any time points accordingly (P＞0.05), the non-fusion group was significantly superior to the fusion group in LSDI score 12 months postoperatively [(7.2±4.1) vs (9.7±3.9), P＜0.05] and at the latest follow-up [(6.8±3.7) vs (8.9±3.6), P＜0.05]. Radiographically, there were no statistically significant differences in preoperative upper adjacent segment range of motion (ROM), fixed segment ROM, total lumbar ROM and Pfirrmann grade for degeneration of the upper adjacent intervertebral disc between the two groups (P＜0.05). However, the non-fusion group had significantly less ROM of the upper adjacent segment at 12 months postoperatively and