Purpose The purpose of this study was to to determine the clinical efficacy of pre-emptive parecoxib in the percutaneous endoscopic lumbar discectomy. Methods A randomized,double blinded study was conducted in which 76 patients were randomly distributed to parecoxib group and placebo group.All participants were estimated by detailed medical history,physical examination,visual analogue scale for back and leg pain,oswestry disability index and modified macnab criteria.Surgery time,blood loss and hospitalization duration were also recorded. Results There was no significant mean age,surgery time,and intraoperatve blood loss differences between the two treatment groups.The hospitalization duration was shorter in parecoxib group than that of placebo group.Complications appeared in 2 patients(5.0%)in the parecoxib group and three patients(8.3%)in the placebo group.87.5%patients exerted excellent and good clinical outcomes in parecoxib group,which was higher than that of placebo group(83.4%).Average improvements of visual analogue scores for back pain,leg pain,and oswestry disability index scores between preoperation and final follow-up were 3.94±0.27,6.80±0.37,52.83±2.85%respectively in parecoxib group,and 3.17±0.24,6.14±0.38,46.1±2.31%respectively in placebo group,the statistical difference was significant. Conclusions The application of pre-emptive parecoxib significantly alleviated postoperative pain,shortened hospitalization period and improved patient satisfaction after percutaneous endoscopic lumbar discectomy.Therefore,pre-emptive parecoxib may be useful in pain relief of the percutaneous endoscopic lumbar discectomy and worth clinical promotion.