Hypertriglyceridaemia is one of the most common causes of severe acute pancreatitis (SAP). However, the association between elevated triglycerides (TG) level in hospital stay and outcome in SAP patients with normal TG level at admission has not been clearly demonstrated. This retrospective study assessed the serum TG levels of patients with SAP admitted to the intensive care unit (ICU) in 2017. Variables with a statistically significant association with the incidence of in-hospital TG elevation, as determined by univariate analysis, were analysed using a logistic regression model to predictors. Of the 99 patients included in the study, TG levels were within the normal range in 59 (59.59%) patients at admission. Among patients with normal TG level when admitted to ICU, 28 (47.46%) experienced at least one episode of TG level elevation during their ICU stay. Elevated TG level in hospitalization is associated with an increased length of ICU stay, as well as increased mortality. In addition to other factors, propofol usage was independently associated with the occurrence of in-hospital-TG elevation. To conclude, we retrospectively investigated the incidence, outcome, and risk factors for in-hospital TG elevation events in SAP patients admitted to the ICU. We found a high incidence of both preexisting and in-hospital-acquired TG elevation in SAP patients admitted to the ICU. The TG elevation that occurred during the ICU stay was associated with worse outcomes and long-term hospitalization of the ICU. Propofol usage was independently associated with the TG elevation occurrence in the ICU.