Objective To investigate the influencing factors of postoperative thirst in post-anesthsia care unit (PACU) patients, and to construct the risk prediction nomogram model and test the prediction effect . Methods A total of 366 patients were admitted to the PACU from December 2023 to March 2024.They were selected and randomly divided into 244 cases in the modeling group and 122 cases in the validation group according to the ratio of 2:1. Thirst was scored using the Numerical Rate Scale (NRS), and the modeling group was divided into thirst group (n=183) and non-thirst group (n=61) according to the score results.Logistic regression was used to analyze risk factors.R software was used to draw the nomogram predictive risk model.Hosmer-Lemeshow test was used to judge the goodness of fit of the model. The area under ROC curve was used to detect the predictive effect of the model.Results The incidence of postoperative thirst in PACU patients in the modeling group was 75.0%, and the risk factors included in the thirst prediction model were age, history of hypertension, ,fasting time,inwelling tracheal tube duration, administration anticholinergic drug (p ＜0.05). The Hosmer-Lemeshow test result of the model showed that p=0.592; the area under the ROC curve was 0.820（0.770～0.880）;the optimal critical value was 0.727;the sensitivity was 0.851;the specificity was 0.810;the accuracy of external validation was 81.97%.They suggested that the model had good fitting and high predictive value .Conclusion The incidence of postoperative thirst is high in PACU patients. The nomogram model constructed in this study can predict the risk of postoperative thirst in PACU patients early and efficiently.It provides a scientific basis for the early assessment and prevention of postoperative thirst.