Abstract: Objective: To construct a nomogram model for predicting postoperative respiratory depression in patients treated with thoracoscopic lung surgery under general anesthesia. Methods: A total of 220 patients treated with thoracoscopic lung surgery under general anesthesia were selected as the study subjects.According to whether respiratory depression occurred after surgery,the patients were divided into the respiratory depression group(41 cases) and non-respiratory depression group(179 cases).The clinical data of patients were collected,and the univariate and multivariate logistic regression analysis were used to evaluate the risk factors of postoperative respiratory depression in patients treated with thoracoscopic lung surgery under general anesthesia.The R language was used to draw a nomogram model,and its prediction efficiency was verified. Results: Among 220 patients,the postoperative respiratory depression in 41 cases was found,and the incidene rate of which was 18.64%.The results of multivariate logistic regression analysis showed that the age ≥60 years,BMI≥28 kg/m²,long operation time and dexmedetomidine use were the independent risk factors of postoperative respiratory depression in patients treated with thoracoscopic lung surgery under general anesthesia(P<0.05 to P<0.01).Based on the results of multivariate regression analysis,a nomogram model was established to predict the risk of postoperative respiratory depression in patients treated with thoracoscopic lung surgery under general anesthesia.The results of model verification results showed that the C-index was 0.801,the correction curve was basically consistent with the ideal curve,the AUC was 0.792 (95%CI:0.754-0.830),and the net benefit value predicted by the column graph was high in the range of 12%-100%,which indicated that the model had good forecasting ability. Conclusions: The age≥60 years,BMI≥28 kg/m²,long operation time and use of dexmedetomidine increase the risk of postoperative respiratory depression in patients treated with thoracoscopic lung surgery under general anesthesia.The clinical model based on nomogram can effectively predict the risk of postoperative respiratory depression in patients treated with thoracoscopic lung surgery under general anesthesia.