Aims: Acute cholangitis is a potentially fatal bacterial illness that poses a significant risk to patients if not promptly addressed, despite the progress made in the field of diagnosis and treatment. Multiple laboratory and clinical data are employed in assessing the severity and fatality rates associated with acute cholangitis. This study aimed to assess the predictive utility of the ratio between elevated laboratory results and albumin levels in determining the severity of disease and mortality rates in patients with cholangitis.Methods: The study comprised a cohort of 471 individuals diagnosed with acute cholangitis, alongside a control group of 150 individuals without acute cholangitis. The patients' information was acquired by conducting a retrospective search of the computerized database. The study collected data on the age, gender, routine laboratory parameters, concomitant disorders, etiology of cholangitis, and outcomes (discharge or death) of all patients. The patients were categorized into three grades, namely grade 1, grade 2, and grade 3, based on the severity of cholangitis, using the Tokyo 2018 standards as a reference.Results: The study comprised a sample size of 621 people. Out of the whole sample size, 53.1% (330 individuals) were identified as male. The study observed a broad range of ages (23-98) with a median age of 67 years, which was found to be greater in the cholangitis group. Among the patients in the cholangitis group, a mortality rate of 6.8% (32 individuals) was observed. A notable disparity was seen in all laboratory parameters between the two groups. The cholangitis group had greater levels of albumin-related ratios, and there was a positive correlation observed between all ratios and the severity of the condition. In deceased individuals, there were greater rates observed for variables other than the γ-glutamyl transferase/albumin ratio (GAR). The results of both univariate and multivariate regression analyses demonstrated a significant correlation between the ratios of direct bilirubin to albumin (DBAR), international normalized ratio to albumin (IAR), neutrophil to albumin (NAR), and mortality. Additionally, the study revealed that the mortality and severity of cholangitis could be predicted by all the albumin-related ratios examined, particularly the INR/albumin ratio (IAR), as indicated by the ROC analysis.Conclusion: It is posited that the utilization of albumin-related ratios, obtainable through routine laboratory testing, may serve as an effective means to assess the severity of acute cholangitis and predict mortality rates associated with the condition. Immediate biliary drainage is recommended for patients with elevated ratios.