BACKGROUND: Acute-on-chronic liver failure (ACLF) is a syndrome with high 28- and 90-day mortality rates. Magnetic resonance imaging (MRI) has been widely used to diagnose and evaluate liver disease. Our purpose is to determine the value of the imaging features derived from Gd-DTPA-enhanced MRI for predicting the poor outcome of patients with ACLF and develop a clinically practical radiological score. METHODS: This retrospective study comprised 175 ACLF patients who underwent Gd-DTPA-enhanced abdominal MRI from January 2017 to December 2021. The primary end-point was 90-day mortality. Imaging parameters, such as diffuse hyperintense of the liver on T2WI, patchy enhancement of the liver at the arterial phase, uneven enhancement of the liver at the portal vein phase, gallbladder wall edema, periportal edema, ascites, esophageal and gastric varix, umbilical vein patefac, portal vein thrombosis, and splenomegaly were screened. Cox proportional hazard regression models were used to evaluate prognostic factors and develop a prediction model. The accuracy of the model was evaluated by receiver operating characteristic (ROC) curves. RESULTS: During the follow-up period, 31 of the 175 ACLF patients died within 90 days. In the multivariate analysis, three imaging parameters were independently associated with survival: diffuse hyperintense on T2WI (p = 0.007; HR = 3.53 [1.40-8.89]), patchy enhancement at the arterial phase (p = 0.037; HR = 2.45 [1.06-5.69]), moderate ascites (vs. mild) (p = 0.006; HR = 4.12 [1.49-11.36]), and severe ascites (vs. mild) (p = 0.005; HR = 4.29 [1.57-11.71]). A practical radiological score was proposed, based on the presence of diffuse hyperintense (7 points), patchy enhancement (5 points), and ascites (6, 8, and 8 points for mild, moderate, and severe, respectively). Further analysis showed that a cut-off at 14 points was optimum to distinguish high-risk (score > 14) from the low-risk group (score ≤ 14) for 90-day survival and demonstrated a mean area under the ROC curve of 0.774 in ACLF patients. CONCLUSIONS: Gd-DTPA-enhanced MR imaging features can predict poor outcomes in patients with ACLF, based on which we proposed a clinically practical radiological score allowing stratification of the 90-day survival.