Objective: Pulmonary embolism (PE) after surgery is a severe thrombotic event for patients suffering from head and neck malignancies. Our study analyzed the factors related to PE in such patients following radical resection. A case-control study was designed to retrospectively investigate the factors associated with the increased risk. Methods: From 2013 to 2022, 5042 radical resections were performed for head and neck malignancies. A control group, matched by age, gender, pathological diagnosis, and cancer stage, but without postoperative PE, was selected in a one-to-three ratio. The perioperative clinical data, encompassing hemodynamic management metrics, were subjected to univariate analyses. Conditional logistic regression modeling was implemented to quantify covariate effects. Results: The prevalence of PE after surgery was 0.75% (95% CI = 0.55-1.03). Multivariable conditional logistic regression revealed PE after surgery was associated with cumulative time of the mean blood pressure (MBP) reductions > 20% (OR = 3.167, 95% CI = 1.651-6.075, p = 0.001), oliguria (OR = 44.055, 95% CI = 2.356-823.886, p = 0.011), and bilateral neck dissection (OR = 3.291, 95% CI = 1.112-9.740, p = 0.031). The maximum area under the curve (AUC) for predicting PE was 0.809 (95% CI 0.716-0.902), achieved using cumulative hypotensive burden (MBP reductions > 20%), with a classification threshold of 1.17 h. Conclusions: Intraoperative hypotension, oliguria, and bilateral neck dissection are significant predictors of postoperative PE following head and neck cancer surgeries. These findings underscore the importance of predictive clinical measures for effective risk control. Level of Evidence3.