Introduction: Pseudomyxoma peritonei (PMP) is a condition characterised by the presence of gelatinous tumour-like growth within the peritoneal cavity. Combined cytoreductive surgery and intraperitoneal chemotherapy have shown to improve the survival rate in PMP patients. However, post-operative complications such as cognitive dysfunction, respiratory insufficiency and acute renal failure are still observed. This retrospective study aims to explore the risk factors associated with major post-operative complications and specifically investigate the correlation with intraoperative hypotension., Patients and Methods: This retrospective cohort study included PMP patients treated at Beijing Aerospace Center Hospital from 1 June, 2014 to 30 December, 2020. The primary outcome measures were major post-operative complications, including neurological, pulmonary, cardiovascular, surgical complications, acute hepatic injury and acute kidney injuries. The secondary outcome measures included infection, fever and deep venous thrombosis. Statistical analysis was conducted using EmpowerStats and R software., Results: A total of 782 patients were screened, and 668 patients were included in the statistical analysis. Amongst them, 234 (35.03%) individuals experienced major post-operative complications. Factors such as pre-operative American Society of Anaesthesiologists grading, age, haemoglobin and albumin levels, intraoperative mean arterial pressure, blood loss, fluid replacement volume, method of intraperitoneal hyperthermic perfusion and post-operative requirement for intensive care unit mechanical ventilation were found to be correlated with major complications., Conclusion: The identified risk factors provide valuable insights for improving clinical pathways in the management of PMP. Further prospective studies are warranted to establish the association between these factors and patient outcomes., (Copyright © 2024 Copyright: © 2024 Journal of Minimal Access Surgery.)