Objective To study the clinical effect of posterior lumbar interbody fusion (PLIF) using expandable cage in treatment of lumbar spondylolisthesis.Methods Twenty patients who underwent PLIF using expandable cage for lumbar spondylolisthesis were retrospectively analyzed.The operative time and transoperative bleeding were recorded.Postoperative regularity follow-up X-ray and CT,the olisthy rate,intervertebral height index and intervertebral fusion were observed.The lumbar function improvement was assessed by Oswestry disability index (ODI).Results All the patients were successfully operated,the operative time was 100-160 (123.3 ± 16.4) min,transoperative bleeding was 350-600 (464.0 ± 78.7) ml.The follow-up time was 12-36 (24.3 ± 7.3) months,symptoms were significantly improved.During the follow-up duration,20 patients obtained bony fusion.According to the reforming Macnab grade standard,excellent was in 14 cases,good was in 4 cases,acceptable was in 2 cases,the rate of excellent and good was 90.0％(18/20).The ODI score and olisthy rate postoperative 6 months and last follow-up were significantly lower than preoperative,and ODI score last follow-up was significantly lower than that postoperative 6 months,there were statistical differences (P ＜ 0.05).The intervertebral height index postoperative 6 months and last follow-up were significantly higher than that preoperative,there were statistical differences (P ＜0.05).There was no statistical difference in olisthy reset rate between postoperative 6 months and last followup (P ＞0.05).The last followed-up,There were no expandable cage subsidence or displacement,intervertebral space collapse and intervertebral height loss.Conclusions As a new production,expandable cage is an effective tool on treating lumbar spondylolisthesis,it can effectively restore the intervertebral height and the biological mechanical properties of the lumbar vertebrae.This study indicates that expandable cage is an effective and safe products for lumbar interbody fusion,which maintained a lower complication rate and better results.