Postoperative pneumonia is common and associated with increased postoperative mortality. Intraoperative hypotension is suggested to be associated with an increased risk of postoperative surgical infection. We aim to explore whether intraoperative hypotension could increase the risk of postoperative pneumonia in adult patients undergoing intracranial tumor resection.A total of 341 patients who received selective intracranial tumor resection under general anesthesia between January 2018, and December 2022 in a single university hospital were reviewed. Univariate and multivariate analyses were performed. The outcomes included the incidence of postoperative pneumonia and the association between intraoperative hypotension and postoperative pneumonia.The incidence of postoperative pneumonia during hospitalization after intracranial tumor resection was 16.8%. Univariate analysis revealed a history of preoperative smoking, intraoperative mean arterial pressure (MAP) < 55 mmHg, American Society of Anesthesiologists classification (ASA) > 2, the duration of surgery > 4 hours, and the duration of controlled ventilation > 4 hours were identified as possible risk factors (P < 0.1). Multivariate analysis revealed a history of preoperative smoking (adjusted odds ratio: 5.205, 95% confidence interval [1.826-14.836], P = 0.003) and intraoperative MAP < 55 mmHg (adjusted odds ratio: 3.082, 95% confidence interval [1.447-6.432], P = 0.003) were independently associated with postoperative pneumonia.Intraoperative hypotension may be associated with postoperative pneumonia in patients who received selective intracranial tumor resection under general anesthesia.©2025 Chang et al.