Background: Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality. A consequence of severe acute pancreatitis is thrombus in the splanchnic veins. These thrombi can potentially lead to bowel ischemia or hepatic failure. However, another complication of severe acute pancreatitis is retroperitoneal bleeding. At this time, it is unclear if treating patients for splanchnic vein thrombosis in the context of severe acute pancreatitis is associated with any outcome benefit. A systematic review might clarify this question. Data sources: A two-fold search strategy (one broad and one precise) looked at all published literature. The review was registered on PROSPERO (ID: CRD42018102705). MEDLINE, EMBASE, PubMed, Cochrane and Web of Science databases were searched and potentially relevant papers were reviewed indepen- dently by two researchers. Any disagreement was reviewed by a third independent researcher. Primary outcome was reestablishment of flow in the thrombosed vein versus bleeding complications. Results: Of 1462 papers assessed, a total of 16 papers were eligible for inclusion. There were no ran- domized controlled trials, 2 were case series, 5 retrospective single-center studies and 9 case reports. There were a total of 198 patients in these studies of whom 92 (46.5％) received anticoagulation therapy. The rates of recanalization of veins in the treated and non-treated groups was 14％ and 11％ and bleeding complications were 16％ and 5％, respectively. However, the included studies were too heterogeneous to undertake a meta-analysis. Conclusions: The systematic review highlights the lack evidence addressing this clinical question. There- fore a randomized controlled trial would be appropriate to undertake.