Objective To assess the clinical effect of Percutaneous transforaminal endoscopic spinal surgery for central lumbar spinal stenosis.Methods Total 92 patients (44 males and 48 females with average age of 68.6± 12.4 years) with central lumbar spinal stenosis were enrolled in our study during February 2012 and July 2016.All patients were treated with Percutaneous transforaminal endoscopic spinal surgery.Clinical and Radiographic evaluation were investigated on 1 week,3 months,6 months,12 months postoperatively and final follow-up.Visual analogue scale (VAS) for low back pain and leg pain,Oswestry disability index(ODI) for low back pain were used to evaluate the clinical efficacy of surgery.Pre and postoperative Dural sac cross sectional area(DSCA) was measured.And the correlation between changes of DSCA and clinical efficacy was analyzed.Results The operation time was 45-1 15 min.The mean operation time was 75±15 min.the mean blood loss was 15±5 ml (range 8-50 ml).All patients were followed for 12-46 months (24.5±5.3 months).VAS for low back pain,VAS for leg pain,and OD1 were significantly improved from 6.75± 1.28,7.79± 1.15 and 39.82％ ±5.06％ preoperatively to 2.21± 1.08,2.16± 1.14 and 9.82％ ±3.69％ at the latest follow-up.Dural sac cross sectional area significantly increased from 55.35±12.18 mm2 preoperatively to (102.36±15.38) mm2 at the latest follow-up.Correlation coefficient with DSCA change was-0.480 for ODI change,-0.612 for VAS(low back pain) change,-0.637 for VAS (leg pain)(P ＜ 0.05);obvious positive correlation existed between the change of DSCA and patient's clinical efficacy.It showed that the change of DSCA was positively correlated with the patient's clinical efficacy.The clinical results were excellent in 56 cases.good in 29,fair in 4,and poor in 3 based on the MacNab criteria.92.39％ demonstrated a good-to-excellent outcome.One case occurred cauterizing syndrome,3 cases of recurrence,and 2 cases of Dural tear.There was no severe vascular or nerve injury.Conclusion Percutaneous transforaminal endoscopic spinal surgery provides a new minimally invasive treatment for central lumbar spinal stenosis.It is safe and effective.It is found that the change of DSCA is positively correlated with the clinical efficacy of surgery.