Hepatic sinusoidal obstruction syndrome (previously named veno-occlusive disease, SOS/VOD) is a serious complication of allogeneic stem cell transplantation (HSCT). Early identification of patients at risk of SOS/VOD may possibly improve the outcome and reduce mortality. Rotation thromboelastometry (ROTEM) is global assay allowing for the precise assessment of both bleeding and thrombotic conditions, however, its usefulness in patients undergoing HSCT for acute leukaemia has not been studied. We evaluated the thromboelastometry parameters in patients undergoing allogeneic HSCT for acute leukaemia to identify candidate biomarkers of SOS/VOD occurrence. ROTEM assays (INTEM, EXTEM, FIBTEM, APTEM) were performed on day -10, on the day of stem cell infusion (day 0) and on days +12 and +28 post-HSCT. The diagnosis of SOS/VOD was based on the Baltimore criteria. Seven patients (26%) developed SOS/VOD. On day +12, the patients with SOS/VOD had statistically significant longer INTEM-CT (clotting time, 199 ± 33.41vs166 ± 23.65s, p = 0.0033), EXTEM-CT (69.5 ± 6.39vs.52 ± 3.42s, p = 0.0139) and FIBTEM-CT (69.5 ± 22.75vs. 50.8 ± 14.31s, p = 0.0124) compared to SOS/VOD (-). ROC curve on day +12 indicated a cut-off value of 179s in INTEM-CT (AUC = 0.91), 69s in EXTEM-CT (AUC = 0.90) and 102s in FIBTEM-CT (AUC = 0.82) for the prediction of SOS/VOD. This is the first study evaluating the usefulness of ROTEM assays in the early detection of haemostasis abnormalities predictive of SOS/VOD development in patients undergoing HSCT for acute leukemia. Patients with SOS/VOD had a significant delay in the initiation of thrombin formation in the analysed ROTEM assays. The utility of ROTEM assays in the optimal management of patients undergoing HSCT should be clarified in further prospective studies.