We tested the diagnostic validity of carbohydrate-deficient transferrin (CDT) as an indicator for relapse into elevated alcohol consumption among patients who were examined under follow-up treatment before (n = 147) and after (n = 102) orthotopic liver transplantation (OLT) in the outpatient-department of the University Hospital Department of Surgery in Hamburg-Eppendorf. CDT measurements were performed with two commercial kits in parallel (CDTect-RIA and CDT%-RIA). Short-term parameters of alcohol consumption (ethanol, methanol) indicated relapses into elevated alcohol consumption in 11.4% of the evaluated patients with alcoholic liver disease (ALD) before transplantation. Before OLT, median CDT values were determined to be elevated among patients with alcoholic as well as nonalcoholic end-stage liver diseases (NALD). Among patients with ALD, we found elevated CDT medians even in those who were successfully scheduled for OLT after long-term evidence of abstinence proved by biochemical short-term parameters and psychological tests. Both CDTect and CDT% assays had comparable low specificities in selected patient groups before transplantation. CDT% and CDTect were negatively correlated with the albumin level. Before the study ended, CDT was no longer implemented in the evaluation of whether an OLT should be administered. This was due to inconsistent results of CDT in ALD as well as NALD. After OLT, patients with ALD, as well as NALD, had statistically significant lower CDT medians than before OLT, which ranged within reference levels. We determined, according to CDT, elevated alcohol consumption subsequent to OLT in 4 of 13 patients with ALD who underwent transplantation during the study (median observation period: 10 months). CDT does not appear to be useful in evaluating patients before OLT. With regained specificity and high sensitivity in patients after OLT, CDT could be recommended as a standard instrument for quality control in patients with ALD after liver transplantation.