ObjectiveTo investigate risk factors for postoperative sore throat in patients with double-lumen endotracheal intubation. MethodsThe data used in this post-hoc analysis were prospectively collected from a randomized， controlled trial. Age from 18 to 65 years old， ASAI-Ⅲ patients undergoing general anesthesia with a double-lumen endotracheal tube were enrolled. The perioperative data collected retrospectively were as follows： gender， age， smoking history， endotracheal tube diameter， duration of endotracheal tube， dose of Sufentanil， use of Flurbiprofen Axetil， cough after extubation， etc..Dynamometer was applied to assess extubation force. According to occurrence of postoperative sore throat， patients were divided into two groups： those who experienced sore throats and those who did not. Comparative analysis and multivariate logistic regression analysis were performed to screen the risk factors. ROC curve was used for predicting the predictive value of risk factors. ResultsAmong the 163 patients ， 74 （45.4%） had postoperative sore throat vs 89 （54.6%） not had. Multivariate logistic regression showed female ［OR95%CI=3.83（1.73， 8.50）， P=0.000 1］ and extubation force ［OR95%CI=1.78（1.45， 2.17）， P＜0.001］ were independent risk factors for postoperative sore throat. AUC value showed the extubation force was 0.773［95%CI（0.701， 0.846）， P＜0.001］. Youden index was 0.447， and the cut-off valve of extubation force was 13N. ConclusionFemale and extubation force were risk factors for sore throat in patients with double lumen endotracheal intubation.