Introduction: Acute kidney injury (AKI) is an important independent predictor of mortality in cirrhotic patients with spontaneous bacterial peritonitis (SBP). However, the definition of AKI in cirrhosis has been debated for many years. This study aims to compare the prediction accuracy of Kidney Disease: Improving Global Outcomes (KDIGO) and International Club of Ascites (ICA) criteria for hospital mortality in cirrhotic patients with SBP admitted to the intensive care unit (ICU). Material and methods: Two hundred and sixteen cirrhotic patients with SBP consecutively admitted to the ICU during 2010-2017 were retrospectively analyzed. Demographic parameters and clinical variables were collected with case report forms. Risk factors for hospital mortality were identified through a multivariate logistic regression analysis. The predictive value of ICA and KDIGO criteria was analyzed by the area under the receiver operating characteristic curve (AUROC). The primary endpoint was hospital mortality. Results: Overall hospital mortality in our population was 73.6%. Incidence of AKI was 83.8% and 81.5% according to the KDIGO and ICA classifications respectively, associated with increased in-hospital and 180-day mortality. The AKI was an independent risk factor for hospital mortality. The risk factor of AKI according to KDIGO was greater than that of ICA. The AUROC for in-hospital mortality for ICA and KDIGO was 0.730 and 0.752, respectively. However, the predictive ability of ICA criteria for in-hospital mortality was non-inferior to that of KDIGO criteria (p = 0.123). Conclusions: Both ICA and KDIGO criteria were good tools with excellent prediction performance for hospital mortality in cirrhotic patients with SBP admitted to the ICU.